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MINI REVIEW article

Front. Pharmacol., 03 October 2022
Sec. Experimental Pharmacology and Drug Discovery
This article is part of the Research Topic Re-emergence of Natural Products for Drug Discovery in Honor of Prof. Dr. M. Iqbal Choudhary View all 14 articles

The bioactivities of sclareol: A mini review

  • 1Key Laboratory of Drug-Targeting and Drug Delivery System of the Education Ministry and Sichuan Province, Engineering Laboratory for Plant-Sourced Drug and Sichuan Research Center for Drug Precision Industrial Technology, West China School of Pharmacy, Sichuan University, Chengdu, China
  • 2State Key Laboratory of Southwestern Chinese Medicine Resources, Chengdu University of Traditional Chinese Medicine, Chengdu, China
  • 3Department of Breast Oncology, Sun Yat-sen University Cancer Center, Guangzhou, China

Sclareol, a diterpene alcohol isolated from the herbal and flavor plant clary sage (Salvia sclarea L.), is far-famed as the predominant ingredient in the refined oil of Salvia sclarea (L.). The empirical medicine of Salvia sclarea L. focused on various diseases, such as arthritis, oral inflammation, digestive system diseases, whereas the sclareol possessed more extensive and characteristic bioactivities, including anti-tumor, anti-inflammation and anti-pathogenic microbes, even anti-diabetes and hypertension. However, there is a deficiency of literature to integrate and illuminate the pharmacological attributes of sclareol based on well-documented investigations. Interestingly, sclareol has been recently considered as the potential candidate against COVID-19 and Parkinson’s disease. Accordingly, the bioactive attributes of sclareol in cancer, inflammation, even pharmacochemistry and delivery systems are reviewed for comprehensively dissecting its potential application in medicine.

Introduction

Salvia sclarea L (SSL, S. sclarea), known as clary sage, plays pivotal role in herb medicine and essential oil industry (Chalvin et al., 2021a). Notably, its essential oil has been investigated for various bioactivities including anti-oxidant, anti-bacterial, anti-fungal, anti-inflammatory, anti-diabetic, and so on (Öğütçü et al., 2008; Yuce et al., 2014; Durgha et al., 2016; Raafat and Habib, 2018). According to the early literatures, S. sclarea was widely applied in the empirical medicine for treatment of various diseases, such as arthritis, oral inflammation, digestive system diseases and dysmenorrhea (Peana and Moretti, 2002; Kostić et al., 2017). The remediation potential of SSL in metal polluted soils has been revealed, especially under Cadmium stress and zinc tolerance (Chand et al., 2015; Dobrikova A. et al., 2021; Dobrikova A. G. et al., 2021).

Sclareol (SCL, Labd-14-ene-8, 13-diol), a diterpene alcohol enriching in capitate oil glands of calyxs, was mainly isolated from inflorescences of Salvia sclarea L (Balinova-Tsvetkova and Tsankova, 1992; Schmiderer et al., 2008; Caissard et al., 2012). It also was indispensable raw materials in the synthesis of Ambrox (ambroxide) (Günnewich et al., 2013). SCL, accounting for about 11.5–15.7% in the essential oil, was produced via the two steps enzymatic reaction of Diterpene Synthase (diTPs) and a class II diTPs to substrate Geranylgeranyl Diphosphate (GGPP) and released from chloroplast (Farka et al., 2005; Caniard et al., 2012; Günnewich et al., 2013; Durgha et al., 2016). The terpenoid compositions content including SCL in S. sclarea were affected by geography, climate, temperature, carbon dioxide, nitrogen, plant lines, etc (Yadav et al., 2010; Kaur et al., 2015; Kumar et al., 2017; Tuttolomondo et al., 2021). SCL also existed in several other plant species, comprising Cistus creticus (Cistaceae), Nicotiana glutinosa (Solanaceae) and Cleome spinosa (Brassicaceae) (Caniard et al., 2012). Recently, SCL was identified one of the components of aromatic extraction products (6.9%) obtained from Nicotiana glutinosa L (Popova et al., 2019). As a natural flavor, SCL is widely used in cosmetics and food industry. Salvia sclarea L is widely planted for the extraction of SCL based on commercial purpose for its high content of SCL. SCL performed antiphotoaging efficacy in vitro, and exhibited wrinkle improvement effect in clinical test (0.02% sclareol-containing cream). Furthermore, SCL inhibited ultraviolet-B inducing MMPs expression and prevented collagen degradation by down-regulating the protein expression of AP-1 transcription factors (Park et al., 2016).

There are three synthesis routes of Ambrox from sclareol, in which the classical commercial route including three reactions and two intermediates sclareolide and ambradiol (Yang et al., 2016). However, the one-pot synthesis was viewed to be convenient and environmentally friendly. Another strategy using strains, containing Cryptococcus albidus and Hyphozyma roseonigra, to transform sclareol to sclareol glycol, and then the latter was converted to Ambrox using chemical conversion (Wang et al., 2019). Here, we first summarized the pharmacological effects and molecular mechanisms underlying of the plant-derived bioactive component SCL for further investigating its role in cancer and other diseases.

Pharmacological activities of sclareol

Anti-cancer effects

As shown in Figure 1 and Table 1, SCL has performed extensive activities against cancer via multiple signaling pathways involving cell proliferation, apoptosis, cell cycle arrest and so on. The SCL performed proliferation-suppressive effects in various cancer cells (50% of inhibitory concentration, IC50 < 50 µm), including lung cancer, colon cancer, breast cancer (Paradissis et al., 2007). In addition, cell viability assay showed that splenocytes obviously ascended after SCL treatment while cell proliferation of K562 was restricted (Noori et al., 2013).

FIGURE 1
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FIGURE 1. Schematic overview of the effects and molecular mechanisms of Sclareol in cancers.

TABLE 1
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TABLE 1. The effects and mechanisms of SCL against various cancers in vivo and in vitro.

Early studies suggested that SCL had anti-proliferation activity on leukemia cells (IC50 below 20 μg/ml at 48 h), induced G0/G1 cycle arrest and DNA cleavage in HL60 cells (Dimas et al., 1999). In breast cancer cell lines MN1 and MDD2, SCL (50,100 µm) triggered the DNA synthesis inhibition, cell cycle arrest in G0/G1 phase and cell apoptosis. Docking investigations in silicon revealed SCL putatively targeted BRCA1 with high binding affinity in natural compounds (Hossain et al., 2022). Besides, the 13-epimer-sclareol exerted antiproliferative effect against MCF-7 cells (IC50 = 11.056 μm) and induced apoptosis (10, 20 μm) (Sashidhara et al., 2007). Cellular study found that SCL induced G1 phase cycle arrest, DNA damage, and led to apoptosis by activating Caspase-3, 8, 9 and cleaved PARP in colon cancer HCT116 cells (100 μm) (Dimas et al., 2007).

The Caveolin-1(Cav1) and Superoxide Dismutase 1(SOD1) were supposed to as potential tumor suppressor and oncogene respectively. In cervical cancer cells, SCL (5–20 μg/ml) induced proliferative inhibition via promoting Cav1 expression and down-regulating SOD1, enhanced sensibility of MCF-7, HepG2, SW480 and SW620 cells to bortezomib. Interestingly, Cav1 was negatively associated with SOD1 through involving the lysosome-mediated degradation of SOD1, the effect was facilitated by SCL(Zhang et al., 2017). Additionally, SCL inhibited proliferation (IC50 = 14 μm), invasion and induced apoptosis (2, 5, 10 µm) in MG63 osteosarcoma cells, with the expression of Ezrin and FAK suppressed (Mo et al., 2016). Another similar study in MG63 cells implicated that SCL performed antiproliferative effect (IC50 = 65.2 µm) and induced apoptosis, G1-phase cell cycle arrest and loss of mitochondrial membrane potential (Wang et al., 2015).

Moreover, the synergistic effect of SCL (50 µm) and cisplatin, doxorubicin and etoposide ameliorated drug sensitivity of breast cancer (Dimas et al., 2006). Furthermore, the up-regulation of P53, BAX, Caspase-8, Caspase-9 and down-regulation of Bcl-2 was perceived to trigger apoptosis in breast cancer MCF-7 under SCL treatment, while SCL inhibited proliferation (IC50 = 27.65 μm) by suppressing the phosphorylation of STAT3, which enhanced by the combination of SCL and cyclophosphamide in the above regulative effect (Afshari et al., 2020). The cisplatin (6 mg/kg) combined with SCL (200 mg/kg) exhibited stronger tumor toxicity than cisplatin or SCL alone in A549 mice model with the down-regulation expression of cisplatin-resistant maker ERCC1. And the combination of SCL (100 μm) and cisplatin (50 μm) showed synergetic effect against survival and invasion of A549 cells. In mechanism, SCL (50, 100 μm) inhibited ERCC1 protein expression to sensitize A549 towards cisplatin treatment through attenuating ERCC1 upstream GSK3β-AP1/Snail and JNK-AP1 axis (Pan et al., 2020).

In vivo, SCL repressed the tumor growth by decreasing IL-4 and increasing IFN-γ level in breast cancer mice model, and notably suppressed the population of T regulatory cells (Treg) in tumor (Noori et al., 2010). SCL restricted tumor growth in xenograft model of small cell lung cancer H1688 cells, inhibited proliferation of H1688 cells and H146 cells with IC50 of 42.14 and 69.96 μm at 24 h respectively. In addition, SCL induced G1 phase cycle arrest with the decreased level of CDK4, Cyclin D, Cyclin E, pRb and the increased level of E2F1. Apoptosis that SCL trigging also been reported with caspase-3 activity promoted and cleaved PARP expression elevated, and SCL elevated p-H2AX, p-ATR and p-Chk1 expression to trigger DNA damage in H1688 cells (25, 50, 100 µM) (Chen H. L. et al., 2020).

Anti-inflammatory effects

The anti-inflammatory effects of Labdane diterpenes through regulating NF- κB, nitric oxide (NO) and arachidonic acid metabolite axis had been reported, comprising andrographolide, andalusol, etc (Tran et al., 2017). As a part of labdane diterpenes family, SCL (intraperitoneal injection, 50 and 100 mg/kg) significantly attenuated inflammatory severity by inhibiting NF-κB translocation and phosphorylation of MAPK signaling in atopic dermatitis -like skin lesions model mice induced by 2,4-dinitrochlorobenzene, with local pro-inflammatory cytokine concentration reduced and T cell activation and cytokine production (IFN-g, IL-4 and IL-17 A) inhibited (Wu et al., 2019). SCL suppressed LPS-induced lung injury in mice via impeding NF-κB, MAPKs and HO-1 signaling transductions (Hsieh et al., 2017).

Additionally, SCL treatment retarded arthritic severities in mice model of rheumatoid arthritis through regulating inflammatory cytokines and the population of Th17 and Th1 cells. In vitro, SCL weakened IL-1β-induced expression of MMP-1, TNF-α, and IL-6 in SW982 cells via attenuating translocation of NF-κB and p38 MAPK/ERK/JNK pathways (Tsai et al., 2018).

Distinguishingly, the SCL induced eryptosis with the dysfunction of membrane phosphatidylserine in human erythrocytes, and partially regulated p38 kinase and casein kinase 1α (Signoretto et al., 2016). Interestingly, SCL inhibited RANKL-induced osteoclastogenesis and osteoclast function in vitro (1–10 μm), which was associated with SCL-triggering the suppression of NF-κB and MAPK/ERK signaling pathways, and prevented ovariectomy -induced mouse model from bone loss in vivo (Jin et al., 2019). SCL has been reported to improve dysmenorrhea and inflammation in dysmenorrhea models in vitro and in vivo via suppressing the Ca2+/MLCK/MLC20 pathway cascades (Wong et al., 2020).

The SCL performed anti-osteoarthritic activities by up-regulating TIMPs and inhibiting iNOS, COX-2 and MMPs expression in interleukin-1β-induced rabbit chondrocytes and knee osteoarthritis model of rabbit (Zhong et al., 2015). Moreover, sclareol (10 mg/kg) was found to ameliorate LPS-induced lung injury in mice through the suppression of NF-κB and MAPK signaling and activation of heme oxygenase-1 (HO-1) expression (Hsieh et al., 2017). In addition, the mechanism research indicated that the anti-inflammatory bioactivity of SCL was contributed to inhibition of inflammatory cytokines and enhancement of antioxidant enzyme activity. Sclareol inhibited the release of NO, TNF-α and MDA in the carrageenan-induced paw edema model, and restricted the cell growth and the expression of NO, iNOS and COX-2 in LPS-stimulated RAW264.7 macrophages (Huang et al., 2012).

Anti-pathogenic microbes

The anti-microbial effect of SCL against Candida yeasts, including C. albicans, C. glabrata, C. parapsilosis, and C. tropicalis was almost equivalent to Fluconazole (Popova et al., 2019). The structure-activity relationship study found that the modification of branched chain and benzene ring in SCL improved its antifungal activity (Ma et al., 2018). Miaofeng et al. reported 20 derivates of SCL, in which compound 16 performed the best fungicidal activity against Curvularia lunata (IC50 = 12.09 μg/ml) and Alternaria brassicae (IC50 = 14.47 μg/ml) comparing with SCL and fungicide thiabendazole (Ma et al., 2015). Moreover, the SCL was first reported to inhibit helminth growth in larval (IC50 ≈ 13 μm), juvenile (IC50 = 5.0 μm), and adult (IC50 = 19.3 μm) stages of Schistosoma mansoni, a pathogen of schistosomiasis. Among 14 derivates of SCL, the most effective compound 12 enhanced cytoxicity against larval (IC50 ≈ 2.2 μm), juvenile (IC50 = 1.7 μm), and adult schistosomes (IC50 = 9.4 μm) by interfering with arachidonic acid metabolism to regulate membrane lipid homeostasis (Crusco et al., 2019). Importantly, the wide-spectrum effect against filoviruses of SCL has been proposed, especially, SCL was considered as Ebola virus (EBOV) entry inhibitor by interfering the viral fusion process (EC50 = 2.4 μm) (Chen Q. et al., 2020). In antibiotic resistance, SCL performed synergistic effect with clindamycin against Methicillin-resistant Staphylococcus aureus (Iobbi et al., 2021). SCL also exerted antifungal synergies with Curcumin towards various fungus, including Candida albicans, C. glabrata, Aspergillus fumigatus (Augostine and Avery, 2022). The derivates of SCL were reported more effective against plant pathogenic fungal A. alternate and A. brassicae than thiabendazole (Ma et al., 2018).

Anti-hypertensive and anti-diabetic effects

The reduction of blood pressure SCL induced was observed in normotensive and hypertensive rats, the phenomenon was probably due to ameliorated vasodilation via NO/cGMP signaling (Campos et al., 2017). The regulation of blood pressure mediated by SCL indicates it may be applied to cardiovascular disease as potential hypotensor. In addition, SCL was viewed as one of the bioactive components in Salvia miltiorrhiza and Dalbergia odorifera against miocardial infarction (Zhao et al., 2022). SCL improved hyperglycemia-induced renal injury (renal dysfunction, fibrosis, and inflammation) to prevent diabetic nephropathy through inducing inactivation of MAPKs and NF-κB pathway (Han et al., 2022).

Pharmacokinetics, derivatives and pharmaceutical

Pharmacokinetic studies suggested that SCL was mainly distributed in extracellular fluid (apparent distribution volume was 21.4 L/kg), and its half-life was short (6.0 h) in rats (intravenous injection, 5.0 mg/kg) (Xiang et al., 2021). The neurotoxicity of free SCL was found in bearing tumor mice of colon cancer HCT116 cells when over 560 mg/kg, whereas 50 mg/kg SCL observed to be ineffective in toxicity (Paradissis et al., 2007). The low bioavailability attributed to its poor water solubility (0.0012 g/L) was considered as the main obstacle limiting its clinical application. The structure modification and nano-delivery systems were imported for enhancing bioactivities and pharmacokinetic properties, such water-solubility and distribution.

The aryl derivatives of SCL were synthesized by Heck coupling reaction for importing aryl in the end of SCL branch chain, in which the compound 15-(4-fluorophenyl)-sclareol (SS-12) exhibited the most effective anti-proliferation activity against PC3 cells (IC50 = 0.082 μm). SS-12 (0.3 μM) reshaped the balance between autophagy and apoptosis by regulating the BH3 domain protein Bcl-2 and Beclin 1. SS-12 (0.1–0.3 μm) induced autophagic cell death with the decreased level of P62 and increased expression of LC3-I, LC3-II, Beclin-1, while triggered apoptosis by blocking the Akt/mTOR pathway in PC-3 Cells (Shakeel u et al., 2015). The tumor growth of Sarcoma-180 Solid and Ascitic Tumors was dramatic suppressed on the group of SS-12 (5, 10 mg/kg i. p.) comparing with the control group treated with 5-fluorouracil (22 mg/kg i. p.) or normal saline.

Highly lipophilic sclareol was encapsulated in PLGA nanoparticles, and then the surface of nanoparticles was modified by hyaluronic acid (HA) to construct HA-NanoSCL for targeting hyaluronic acid receptor in breast cancer. The HA-NanoSCL nanosystem enhanced cytotoxicity against MCF-7 and MDA-MB-468 (0–50 µm) and uptake of SCL in MDA-MB-231 cells (Cosco et al., 2019). Interestingly, The natural and environmental-friendly nano-formulation was reported that SCLAREIN (SCL encapsulated by plant protein zein) with mean size of 120 nm, performed great stability and time-dependent release in 1 week, while the nanoparticles (loading 1 mg/ml SCL) possessed stronger cytoxicity of MCF-7 and K562 than free SCL (Gagliardi et al., 2021).

The liposome, lipid nanoparticles (LNPs) and nanostructured lipidic carriers (NLCs) have been viewed as carriers for lipophilic SCL delivery based on SCL low water solubility and high lipophilicity. Liposomes targeting mitochondria significantly improved the apoptosis induction and cytotoxicity of SCL (Patel et al., 2010). Moreover, liposome SCL increased the distribution of SCL in the nucleus of colon cancer HCT-116 cells (Paradissis et al., 2007) and reduced the tumor growth in HCT116 xenograft mice (Dimas et al., 2007). Solid lipid nanoparticles (SLN) loading with SCL exerted excellent physicochemical features including encapsulation efficiency (EE, 89%) and drug loading (DL, 42.47 mg/g), and realized sustained drug release over 1 week and time-dependent proliferative inhibition in A549 cells comparing with plain SCL (IC50 = 19 μg/ml) (Hamishehkar et al., 2018). Similarly, SLN encapsulated adriamycin and SCL enhanced the antitumor effect of doxorubicin compared with free adriamycin in breast cancer 4T1 cells (Oliveira et al., 2018).

To conquer the drug resistance in cancer and facilitate chemotherapy response, combination therapy has been widely used in clinical and basic investigation. SCL was reported as an enhancer of doxorubicin (DOX) and the combination of DOX and SCL showed stronger anti-proliferative effect than free DOX and free SCL in breast cancer MDA-MB-231 and 4T1 cells. In 4T1 mice model, the nanostructured lipid carrier loading Doxorubicin and SCL (NLC-DOX-SC) exhibited better tumor inhibition than plain DOX and NCL-DOX, also performed lower cytoxicity than the combination of free DOX and SCL in weight loss and myelosuppression (Borges et al., 2019). However, recent research indicated that NLC-SCL exerted higher encapsulation than SLN-SCL, which was contributed to the difference of lipid matrix (Borges et al., 2021). NLC-SCL performed higher anti-proliferation effect than plain SCL against MDA-MB-231 and HCT-116 cells. Moreover, NLC-SCL G2/M phase arrest in above cells (Borges et al., 2021). Variously, sclareol-loaded lipid nanoparticles effectively improved metabolism and attenuated obesity process in obesity induced mice, which was attributed to the decreased expression of proinflammatory cytokines (NF-kB and MCP-1) and adipogenesis related markers SREBP-1 (Cerri et al., 2019).

Conclusion and prospect

Although sclareol has exhibited extensive and wide-spectrum effects for attenuating cancer-related phenotypes, such as proliferation, apoptosis and cell cycle, the molecular pathways sclareol mediated remain uncharted and the present studies focusing on signaling mechanisms are not deep and comprehensive. For instance, weather SCL is associated with ferroptosis and pyroptosis, and the relationship between SCL with m6A RNA methylation remains underlying. Investigations on structure activity relationships provide new sight to uncover the bioactivities between SCL and its analogues, while the improvement of pharmacokinetic parameters (water solubility and half-life) and targeting are entitled by delivery systems, including liposome, lipid nanoparticle, etc. Beyond anti-tumor effects, SCL also exhibited other attributes, mainly comprising anti-inflammation and anti-pathogenic microbes (fungal, schistosomiasis and Ebola virus). The classic NF-κB and MAPK signaling pathways exerts crucial role in the anti-inflammation property of SCL. It is significant that SCL triggered immunomodulatory effects of Th17, Th1 and Treg may involve tumor microenvironment remodeling. Promisingly, SCL was identified as a novel Cav1.3 antagonist against Parkinson’s disease (Wang et al., 2022). SCL was considered as candidate drug to treat or prevent SARS-CoV-2 via targeting Covid19 Main Protase (MPro) (Aydın et al., 2021). Sclareol as F1Fo-ATP synthase inhibitor restrained free radical production in the retinal rod, which indicated SCL could serve as a potential drug for retinal disease (Ravera et al., 2020).

Biosynthetic strategy provided new application prospect for industrial manufacture of sclareol with green and sustainable, compared to traditional extract from plants (Einhaus et al., 2022). We look forward emerging investigations to further explore the role of sclareol in combined therapy with chemotherapy or immunotherapy against cancer, even in Covid19 and Parkinson’s disease.

Author contributions

The manuscript was written by JZ, XX, and HT revised the manuscript. CP and FP supported the study.

Funding

The study was supported by the National Natural Science Foundation of China (no.82003879 and U19A2010) the Key Project of Science and Technology Department of Sichuan Province (no. 2020YFS0053; 2021YFS0044), and Youth Talent Promotion Project of China Association for Science and Technology (CACM-2020-QNRC1-01), Project of State Administration of Traditional Chinese Medicine of China (ZYYCXTD-D-202209) and the Open Research Fund of Chengdu University of Traditional Chinese Medicine Key Laboratory of Systematic Research of Distinctive Chinese Medicine Resources in Southwest China.

Conflict of interest

The authors declare that the research was conducted in the absence of any commercial or financial relationships that could be construed as a potential conflict of interest.

Publisher’s note

All claims expressed in this article are solely those of the authors and do not necessarily represent those of their affiliated organizations, or those of the publisher, the editors and the reviewers. Any product that may be evaluated in this article, or claim that may be made by its manufacturer, is not guaranteed or endorsed by the publisher.

References

Afshari, H., Nourbakhsh, M., Salehi, N., Mahboubi_Rabbani, M., Zarghi, A., and Noori, S. (2020). STAT3-mediated apoptotic-enhancing function of sclareol against breast cancer cells and cell sensitization to cyclophosphamide. Iran. J. Pharm. Res. 19 (1), 398–412. doi:10.22037/ijpr.2020.112587.13843

PubMed Abstract | CrossRef Full Text | Google Scholar

Augostine, C. R., and Avery, S. V. (2022). Discovery of natural products with antifungal potential through combinatorial synergy. Front. Microbiol. 13, 866840. doi:10.3389/fmicb.2022.866840

CrossRef Full Text | Google Scholar

Aydın, A. D., Altınel, F., Erdoğmuş, H., and Son Ç, D. (2021). Allergen fragrance molecules: A potential relief for COVID-19. BMC Complement. Med. Ther. 21 (1), 41. doi:10.1186/s12906-021-03214-4

CrossRef Full Text | Google Scholar

Balinova-Tsvetkova, A., and Tsankova, P. (1992). On the extraction of salvia sclarea L. Flavour Fragr. J. 7 (3), 151–154. doi:10.1002/ffj.2730070310

CrossRef Full Text | Google Scholar

Borges, G. S. M., Prazeres, P., de Souza, A. M., Yoshida, M. I., Vilela, J. M. C., Silva, A., et al. (2021). Nanostructured lipid carriers as a novel tool to deliver sclareol: Physicochemical characterisation and evaluation in human cancer cell lines. Braz. J. Pharm. Sci. 57. doi:10.1590/s2175-97902020000418497

CrossRef Full Text | Google Scholar

Borges, G. S. M., Silva, J. d. O., Fernandes, R. S., de Souza, Â. M., Cassali, G. D., Yoshida, M. I., et al. (2019). Sclareol is a potent enhancer of doxorubicin: Evaluation of the free combination and co-loaded nanostructured lipid carriers against breast cancer. Life Sci. 232, 116678. doi:10.1016/j.lfs.2019.116678

PubMed Abstract | CrossRef Full Text | Google Scholar

Caissard, J. C., Olivier, T., Delbecque, C., Palle, S., Garry, P. P., Audran, A., et al. (2012). Extracellular localization of the diterpene sclareol in clary sage (Salvia sclarea L., Lamiaceae). PLoS One 7 (10), e48253. doi:10.1371/journal.pone.0048253

PubMed Abstract | CrossRef Full Text | Google Scholar

Campos, D. R., Celotto, A. C., Albuquerque, A. A. S., Ferreira, L. G., Monteiro, A., Coelho, E. B., et al. (2017). The diterpene sclareol vascular effect in normotensive and hypertensive rats. Arq. Bras. Cardiol. 109 (2), 0–122. doi:10.5935/abc.20170086

CrossRef Full Text | Google Scholar

Caniard, A., Zerbe, P., Legrand, S., Cohade, A., Valot, N., Magnard, J.-L., et al. (2012). Discovery and functional characterization of two diterpene synthases for sclareol biosynthesis in Salvia sclarea(L.) and their relevance for perfume manufacture. BMC Plant Biol. 12 (1), 119. doi:10.1186/1471-2229-12-119

PubMed Abstract | CrossRef Full Text | Google Scholar

Cerri, G. C., Lima, L. C. F., Lelis, D. d. F., Barcelos, L. d. S., Feltenberger, J. D., Mussi, S. V., et al. (2019). Sclareol-loaded lipid nanoparticles improved metabolic profile in obese mice. Life Sci. 218, 292–299. doi:10.1016/j.lfs.2018.12.063

PubMed Abstract | CrossRef Full Text | Google Scholar

Chalvin, C., Drevensek, S., Chollet, C., Gilard, F., Šolić, E. M., Dron, M., et al. (2021a). Study of the genetic and phenotypic variation among wild and cultivated clary sages provides interesting avenues for breeding programs of a perfume, medicinal and aromatic plant. PLoS One 16 (7), e0248954. doi:10.1371/journal.pone.0248954

PubMed Abstract | CrossRef Full Text | Google Scholar

Chand, S., Yaseen, M., and Rajkumari Patra, D. D. (2015). Application of heavy metal rich tannery sludge on sustainable growth, yield and metal accumulation by clarysage (salvia sclarea L.). Int. J. Phytoremediation 17 (12), 1171–1176. doi:10.1080/15226514.2015.1045128

PubMed Abstract | CrossRef Full Text | Google Scholar

Chen, H. L., Gong, J. Y., Lin, S.-C., Li, S., Chiang, Y.-C., Hung, J.-H., et al. (2020a). Effects of sclareol against small cell lung carcinoma and the related mechanism: In vitro and in vivo studies. Anticancer Res. 40 (9), 4947–4960. doi:10.21873/anticanres.14498

CrossRef Full Text | Google Scholar

Chen, Q., Tang, K., and Guo, Y. (2020b). Discovery of sclareol and sclareolide as filovirus entry inhibitors. J. Asian Nat. Prod. Res. 22 (5), 464–473. doi:10.1080/10286020.2019.1681407

PubMed Abstract | CrossRef Full Text | Google Scholar

Cosco, D., Mare, R., Paolino, D., Salvatici, M. C., Cilurzo, F., and Fresta, M. (2019). Sclareol-loaded hyaluronan-coated PLGA nanoparticles: Physico-chemical properties and in vitro anticancer features. Int. J. Biol. Macromol. 132, 550–557. doi:10.1016/j.ijbiomac.2019.03.241

PubMed Abstract | CrossRef Full Text | Google Scholar

Crusco, A., Whiteland, H., Baptista, R., Forde-Thomas, J. E., Beckmann, M., Mur, L. A. J., et al. (2019). Antischistosomal properties of sclareol and its heck-coupled derivatives: Design, synthesis, biological evaluation, and untargeted metabolomics. ACS Infect. Dis. 5 (7), 1188–1199. doi:10.1021/acsinfecdis.9b00034

PubMed Abstract | CrossRef Full Text | Google Scholar

Dimas, K., Hatziantoniou, S., Tseleni, S., Khan, H., Georgopoulos, A., Alevizopoulos, K., et al. (2007). Sclareol induces apoptosis in human HCT116 colon cancer cells in vitro and suppression of HCT116 tumor growth in immunodeficient mice. Apoptosis 12 (4), 685–694. doi:10.1007/s10495-006-0026-8

PubMed Abstract | CrossRef Full Text | Google Scholar

Dimas, K., Kokkinopoulos, D., Demetzos, C., Vaos, B., Marselos, M., Malamas, M., et al. (1999). The effect of sclareol on growth and cell cycle progression of human leukemic cell lines. Leuk. Res. 23 (3), 217–234. doi:10.1016/s0145-2126(98)00134-9

PubMed Abstract | CrossRef Full Text | Google Scholar

Dimas, K., Papadaki, M., Tsimplouli, C., Hatziantoniou, S., Alevizopoulos, K., Pantazis, P., et al. (2006). Labd-14-ene-8, 13-diol (sclareol) induces cell cycle arrest and apoptosis in human breast cancer cells and enhances the activity of anticancer drugs. Biomed. Pharmacother. 60 (3), 127–133. doi:10.1016/j.biopha.2006.01.003

PubMed Abstract | CrossRef Full Text | Google Scholar

Dobrikova, A., Apostolova, E., Hanć, A., Yotsova, E., Borisova, P., Sperdouli, I., et al. (2021a). Tolerance mechanisms of the aromatic and medicinal plant salvia sclarea L. To excess zinc. Plants 10 (2), 194. doi:10.3390/plants10020194

CrossRef Full Text | Google Scholar

Dobrikova, A. G., Apostolova, E. L., Hanć, A., Yotsova, E., Borisova, P., Sperdouli, I., et al. (2021b). Cadmium toxicity in Salvia sclarea L.: An integrative response of element uptake, oxidative stress markers, leaf structure and photosynthesis. Ecotoxicol. Environ. Saf. 209, 111851. doi:10.1016/j.ecoenv.2020.111851

PubMed Abstract | CrossRef Full Text | Google Scholar

Durgha, H., Thirugnanasampandan, R., Ramya, G., and Ramanth, M. G. (2016). Inhibition of inducible nitric oxide synthase gene expression (iNOS) and cytotoxic activity of Salvia sclarea L. essential oil. J. King Saud Univ. - Sci. 28 (4), 390–395. doi:10.1016/j.jksus.2015.11.001

CrossRef Full Text | Google Scholar

Einhaus, A., Steube, J., Freudenberg, R. A., Barczyk, J., Baier, T., and Kruse, O. (2022). Engineering a powerful green cell factory for robust photoautotrophic diterpenoid production. Metab. Eng. 73, 82–90. doi:10.1016/j.ymben.2022.06.002

PubMed Abstract | CrossRef Full Text | Google Scholar

Farka, P., Hollá, M., Tekel, J., Mellen, S., and Vaverková, t. (2005). Composition of the essential oils from the flowers and leaves of salvia sclarea L. (Lamiaceae) cultivated in Slovak republic. J. Essent. Oil Res. 17 (2), 141–144. doi:10.1080/10412905.2005.9698858

PubMed Abstract | CrossRef Full Text | Google Scholar

Gagliardi, A., Voci, S., Bonacci, S., Iriti, G., Procopio, A., Fresta, M., et al. (2021). SCLAREIN (SCLAREol contained in zeIN) nanoparticles: Development and characterization of an innovative natural nanoformulation. Int. J. Biol. Macromol. 193, 713–720. doi:10.1016/j.ijbiomac.2021.10.184

PubMed Abstract | CrossRef Full Text | Google Scholar

Günnewich, N., Higashi, Y., Feng, X., Choi, K.-B., Schmidt, J., and Kutchan, T. M. (2013). A diterpene synthase from the clary sage Salvia sclarea catalyzes the cyclization of geranylgeranyl diphosphate to (8R)-hydroxy-copalyl diphosphate. Phytochemistry 91, 93–99. doi:10.1016/j.phytochem.2012.07.019

PubMed Abstract | CrossRef Full Text | Google Scholar

Hamishehkar, H., Bahadori, M. B., Vandghanooni, S., Eskandani, M., Nakhlband, A., and Eskandani, M. (2018). Preparation, characterization and anti-proliferative effects of sclareol-loaded solid lipid nanoparticles on A549 human lung epithelial cancer cells. J. Drug Deliv. Sci. Technol. 45, 272–280. doi:10.1016/j.jddst.2018.02.017

CrossRef Full Text | Google Scholar

Han, X., Zhang, J., Zhou, L., Wei, J., Tu, Y., Shi, Q., et al. (2022). Sclareol ameliorates hyperglycemia-induced renal injury through inhibiting the MAPK/NF-κB signaling pathway. Phytother. Res. 36 (6), 2511–2523. doi:10.1002/ptr.7465

PubMed Abstract | CrossRef Full Text | Google Scholar

Hossain, R., Ray, P., Sarkar, C., Islam, M. S., Khan, R. A., Khalipha, A. B. R., et al. (2022). Natural compounds or their derivatives against breast cancer: A computational study. Biomed. Res. Int. 2022, 5886269. doi:10.1155/2022/5886269

CrossRef Full Text | Google Scholar

Hsieh, Y.-H., Deng, J.-S., Pan, H.-P., Liao, J.-C., Huang, S.-S., and Huang, G.-J. (2017). Sclareol ameliorate lipopolysaccharide-induced acute lung injury through inhibition of MAPK and induction of HO-1 signaling. Int. Immunopharmacol. 44, 16–25. doi:10.1016/j.intimp.2016.12.026

PubMed Abstract | CrossRef Full Text | Google Scholar

Huang, G.-J., Pan, C.-H., and Wu, C.-H. (2012). Sclareol exhibits anti-inflammatory activity in both lipopolysaccharide-stimulated macrophages and the λ-carrageenan-induced paw edema model. J. Nat. Prod. 75 (1), 54–59. doi:10.1021/np200512a

PubMed Abstract | CrossRef Full Text | Google Scholar

Iobbi, V., Brun, P., Bernabé, G., Dougué Kentsop, R. A., Donadio, G., Ruffoni, B., et al. (2021). Labdane diterpenoids from salvia tingitana etl. Synergize with clindamycin against methicillin-resistant Staphylococcus aureus. Molecules 26 (21), 6681. doi:10.3390/molecules26216681

CrossRef Full Text | Google Scholar

Jin, H., Shao, Z., Wang, Q., Miao, J., Bai, X., Liu, Q., et al. (2019). Sclareol prevents ovariectomy-induced bone loss in vivo and inhibits osteoclastogenesis in vitro via suppressing NF-κB and MAPK/ERK signaling pathways. Food Funct. 10 (10), 6556–6567. doi:10.1039/C9FO00206E

PubMed Abstract | CrossRef Full Text | Google Scholar

Kaur, T., Bhat, H. A., Bhat, R., Kumar, A., Bindu, K., Koul, S., et al. (2015). Physio-chemical and antioxidant profiling of Salvia sclarea L. at different climates in north-Western Himalayas. Acta Physiol. Plant. 37 (7), 132. doi:10.1007/s11738-015-1879-7

CrossRef Full Text | Google Scholar

Kostić, M., Kitić, D., Petrović, M. B., Jevtović-Stoimenov, T., Jović, M., Petrović, A., et al. (2017). Anti-inflammatory effect of the Salvia sclarea L. ethanolic extract on lipopolysaccharide-induced periodontitis in rats. J. Ethnopharmacol. 199, 52–59. doi:10.1016/j.jep.2017.01.020

PubMed Abstract | CrossRef Full Text | Google Scholar

Kumar, R., Kaundal, M., Sharma, S., Thakur, M., Kumar, N., Kaur, T., et al. (2017). Effect of elevated [CO2] and temperature on growth, physiology and essential oil composition of Salvia sclarea L. in the Western Himalayas. J. Appl. Res. Med. Aromatic Plants 6, 22–30. doi:10.1016/j.jarmap.2017.01.001

PubMed Abstract | CrossRef Full Text | Google Scholar

Ma, M., Feng, J., Li, R., Chen, S.-W., and Xu, H. (2015). Synthesis and antifungal activity of ethers, alcohols, and iodohydrin derivatives of sclareol against phytopathogenic fungi in vitro. Bioorg. Med. Chem. Lett. 25 (14), 2773–2777. doi:10.1016/j.bmcl.2015.05.013

PubMed Abstract | CrossRef Full Text | Google Scholar

Ma, M., Feng, J., Wang, D., Chen, S. W., and Xu, H. (2018). Synthesis and antifungal activities of drimane-amide derivatives from sclareol. Comb. Chem. High. Throughput Screen. 21 (7), 501–509. doi:10.2174/1386207321666180925164358

PubMed Abstract | CrossRef Full Text | Google Scholar

Mo, J. W., Yang, R. Z., and Zhang, D. F. (2016). Modulation of anoikis resistance in MG63 osteosarcoma cells by sclareol via inhibiting Ezrin/Fak expression. Int. J. Clin. Exp. PATHOLOGY 9 (7), 6795–6803.

Google Scholar

Noori, S., Hassan, Z. M., Mohammadi, M., Habibi, Z., Sohrabi, N., and Bayanolhagh, S. (2010). Sclareol modulates the Treg intra-tumoral infiltrated cell and inhibits tumor growth in vivo. Cell. Immunol. 263 (2), 148–153. doi:10.1016/j.cellimm.2010.02.009

PubMed Abstract | CrossRef Full Text | Google Scholar

Noori, S., Hassan, Z. M., and Salehian, O. (2013). Sclareol reduces CD4+CD25+FoxP3+T-reg cells in a breast cancer model in vivo. Iran. J. Immunol. 10 (1), 10–21.

PubMed Abstract | CrossRef Full Text | Google Scholar

Öğütçü, H., Sökmen, A., Sökmen, M., Polissiou, M., Serkedjieva, J., Daferera, D., et al. (2008). Bioactivities of the various extracts and essential oils of Salvia limbata C.A.Mey. and Salvia sclarea L.. Turk. J. Biol. 32 (3), 181–192.

Google Scholar

Oliveira, M. S., Lima, B. H. S., Goulart, G. A. C., Mussi, S. V., Borges, G. S. M., Orefice, R. L., et al. (2018). Improved cytotoxic effect of doxorubicin by its combination with sclareol in solid lipid nanoparticle suspension. J. Nanosci. Nanotechnol. 18 (8), 5609–5616. doi:10.1166/jnn.2018.15418

PubMed Abstract | CrossRef Full Text | Google Scholar

Pan, C.-H., Chen, S.-Y., Wang, J.-Y., Tsao, S.-P., Huang, H.-Y., Wei-Chen Chiu, P., et al. (2020). Sclareol ameliorated ERCC1-mediated cisplatin resistance in A549 human lung adenocarcinoma cells and a murine xenograft tumor model by suppressing AKT-GSK3β-AP1/Snail and JNK-AP1 pathways. Chem. Biol. Interact. 332, 109304. doi:10.1016/j.cbi.2020.109304

PubMed Abstract | CrossRef Full Text | Google Scholar

Paradissis, A., Hatziantoniou, S., Georgopoulos, A., Psarra, A.-M. G., Dimas, K., and Demetzos, C. (2007). Liposomes modify the subcellular distribution of sclareol uptake by HCT-116 cancer cell lines. Biomed. Pharmacother. 61 (2-3), 120–124. doi:10.1016/j.biopha.2006.10.006

PubMed Abstract | CrossRef Full Text | Google Scholar

Park, J.-E., Lee, K.-E., Jung, E., Kang, S., and Kim, Y. J. (2016). Sclareol isolated from Salvia officinalis improves facial wrinkles via an antiphotoaging mechanism. J. Cosmet. Dermatol. 15 (4), 475–483. doi:10.1111/jocd.12239

PubMed Abstract | CrossRef Full Text | Google Scholar

Patel, N. R., Hatziantoniou, S., Georgopoulos, A., Demetzos, C., Torchilin, V. P., Weissig, V., et al. (2010). Mitochondria-targeted liposomes improve the apoptotic and cytotoxic action of sclareol. J. Liposome Res. 20 (3), 244–249. doi:10.3109/08982100903347931

PubMed Abstract | CrossRef Full Text | Google Scholar

Peana, A. T., and Moretti, M. D. L. (2002). “Pharmacological activities and applications of Salvia sclarea and Salvia desoleana essential oils,” in Studies in natural products chemistry. Editor R. Atta ur (Elsevier), 391–423.

CrossRef Full Text | Google Scholar

Popova, V., Ivanova, T., Stoyanova, A., Nikolova, V., Hristeva, T., Gochev, V., et al. (2019). Terpenoids in the essential oil and concentrated aromatic products obtained from Nicotiana glutinosa L. Leaves. Molecules 25 (1), E30. doi:10.3390/molecules25010030

PubMed Abstract | CrossRef Full Text | Google Scholar

Raafat, K., and Habib, J. (2018). Phytochemical compositions and antidiabetic potentials of Salvia sclarea L. Essential oils. J. Oleo Sci. 67 (8), 1015–1025. doi:10.5650/jos.ess17187

PubMed Abstract | CrossRef Full Text | Google Scholar

Ravera, S., Esposito, A., Degan, P., Caicci, F., Calzia, D., Perrotta, E., et al. (2020). Sclareol modulates free radical production in the retinal rod outer segment by inhibiting the ectopic f1fo-atp synthase. Free Radic. Biol. Med. 160, 368–375. doi:10.1016/j.freeradbiomed.2020.08.014

PubMed Abstract | CrossRef Full Text | Google Scholar

Sashidhara, K. V., Rosaiah, J. N., Kumar, A., Bid, H. K., Konwar, R., and Chattopadhyay, N. (2007). Cell growth inhibitory action of an unusual labdane diterpene, 13-epi-Sclareol in breast and uterine cancers in vitro. Phytother. Res. 21 (11), 1105–1108. doi:10.1002/ptr.2205

PubMed Abstract | CrossRef Full Text | Google Scholar

Schmiderer, C., Grassi, P., Novak, J., Weber, M., and Franz, C. (2008). Diversity of essential oil glands of clary sage (Salvia sclarea L., Lamiaceae). Plant Biol. 10 (4), 433–440. doi:10.1111/j.1438-8677.2008.00053.x

PubMed Abstract | CrossRef Full Text | Google Scholar

Shakeel u, R., Rah, B., Lone, S. H., Rasool, R. U., Farooq, S., Nayak, D., et al. (2015). Design and synthesis of antitumor heck-coupled sclareol analogues: Modulation of BH3 family members by SS-12 in autophagy and apoptotic cell death. J. Med. Chem. 58 (8), 3432–3444. doi:10.1021/jm501942m

CrossRef Full Text | Google Scholar

Signoretto, E., Laufer, S. A., and Lang, F. (2016). Stimulating effect of sclareol on suicidal death of human erythrocytes. Cell. Physiol. biochem. 39 (2), 554–564. doi:10.1159/000445647

PubMed Abstract | CrossRef Full Text | Google Scholar

Tran, Q. T. N., Wong, W. S. F., and Chai, C. L. L. (2017). Labdane diterpenoids as potential anti-inflammatory agents. Pharmacol. Res. 124, 43–63. doi:10.1016/j.phrs.2017.07.019

PubMed Abstract | CrossRef Full Text | Google Scholar

Tsai, S.-W., Hsieh, M.-C., Li, S., Lin, S.-C., Wang, S.-P., Lehman, C. W., et al. (2018). Therapeutic potential of sclareol in experimental models of rheumatoid arthritis. Int. J. Mol. Sci. 19 (5), E1351. doi:10.3390/ijms19051351

PubMed Abstract | CrossRef Full Text | Google Scholar

Tuttolomondo, T., Virga, G., Licata, M., Iacuzzi, N., Farruggia, D., and Bella, S. L. (2021). Assessment of production and qualitative characteristics of different populations of salvia sclarea L. Found in sicily (Italy). Agronomy 11 (8), 1508. doi:10.3390/agronomy11081508

PubMed Abstract | CrossRef Full Text | Google Scholar

Wang, H., Xie, M., Rizzi, G., Li, X., Tan, K., and Fussenegger, M. (2022). Identification of sclareol as a natural neuroprotective Ca(v) 1.3-antagonist using synthetic Parkinson-mimetic gene circuits and computer-aided drug Discovery. Adv. Sci. 9 (7), e2102855. doi:10.1002/advs.202102855

PubMed Abstract | CrossRef Full Text | Google Scholar

Wang, L., He, H. S., Yu, H. L., Zeng, Y., Han, H., He, N., et al. (2015). Sclareol, a plant diterpene, exhibits potent antiproliferative effects via the induction of apoptosis and mitochondrial membrane potential loss in osteosarcoma cancer cells. Mol. Med. Rep. 11 (6), 4273–4278. doi:10.3892/mmr.2015.3325

PubMed Abstract | CrossRef Full Text | Google Scholar

Wang, X., Zhang, X., Yao, Q., Hua, D., and Qin, J. (2019). Comparative proteomic analyses of Hyphozyma roseonigra ATCC 20624 in response to sclareol. Braz. J. Microbiol. 50 (1), 79–84. doi:10.1007/s42770-019-00040-2

PubMed Abstract | CrossRef Full Text | Google Scholar

Wong, J., Chiang, Y. F., Shih, Y. H., Chiu, C. H., Chen, H. Y., Shieh, T. M., et al. (2020). Salvia sclarea L. Essential oil extract and its antioxidative phytochemical sclareol inhibit oxytocin-induced uterine hypercontraction dysmenorrhea model by inhibiting the Ca(2+)-MLCK-MLC20 signaling cascade: An ex vivo and in vivo study. Antioxidants (Basel) 9 (10), E991. doi:10.3390/antiox9100991

PubMed Abstract | CrossRef Full Text | Google Scholar

Wu, P.-C., Chuo, W.-H., Li, S.-C., Lehman, C. W., Lien, C. Z., Wu, C.-S., et al. (2019). Sclareol attenuates the development of atopic dermatitis induced by 2, 4-dinitrochlorobenzene in mice. Immunopharmacol. Immunotoxicol. 41 (1), 109–116. doi:10.1080/08923973.2018.1555846

PubMed Abstract | CrossRef Full Text | Google Scholar

Xiang, Z., Chen, Y., Xiao, Q., Yu, X., Yu, X., Hu, Z., et al. (2021). GC-MS/MS method for determination and pharmacokinetics of sclareol in rat plasma after intravenous administration. J. Chromatogr. B Anal. Technol. Biomed. Life Sci. 1173, 122703. doi:10.1016/j.jchromb.2021.122703

CrossRef Full Text | Google Scholar

Yadav, A., Chanotiya, C. S., and Singh, A. K. (2010). Terpenoid compositions and enantio-differentiation of linalool and sclareol in salvia sclarea L. From three different climatic regions in India. J. Essent. Oil Res. 22 (6), 589–592. doi:10.1080/10412905.2010.9700406

CrossRef Full Text | Google Scholar

Yang, S., Tian, H., Sun, B., Liu, Y., Hao, Y., and Lv, Y. (2016). One-pot synthesis of (-)-Ambrox. Sci. Rep. 6, 32650. doi:10.1038/srep32650

PubMed Abstract | CrossRef Full Text | Google Scholar

Yuce, E., Yildirim, N., Yildirim, N. C., Paksoy, M. Y., and Bagci, E. (2014). Essential oil composition, antioxidant and antifungal activities of salvia sclarea L. From munzur valley in tunceli, Turkey. Cell. Mol. Biol. 60 (2), 1–5.

PubMed Abstract | Google Scholar

Zhang, T., Wang, T., and Cai, P. (2017). Sclareol inhibits cell proliferation and sensitizes cells to the antiproliferative effect of bortezomib via upregulating the tumor suppressor caveolin-1 in cervical cancer cells. Mol. Med. Rep. 15 (6), 3566–3574. doi:10.3892/mmr.2017.6480

PubMed Abstract | CrossRef Full Text | Google Scholar

Zhao, S., Liu, K., Duan, J., Tao, X., Li, W., Bai, Y., et al. (2022). Identification of traditional Chinese drugs containing active ingredients for treating myocardial infarction and analysis of their therapeutic mechanisms by network pharmacology and molecular docking. Nan Fang. Yi Ke Da Xue Xue Bao 42 (1), 13–25. doi:10.12122/j.issn.1673-4254.2022.01.02

PubMed Abstract | CrossRef Full Text | Google Scholar

Zhong, Y., Huang, Y., Santoso, M. B., and Wu, L.-D. (2015). Sclareol exerts anti-osteoarthritic activities in interleukin-1β-induced rabbit chondrocytes and a rabbit osteoarthritis model. Int. J. Clin. Exp. Pathol. 8 (3), 2365–2374.

PubMed Abstract | Google Scholar

Keywords: sclareol, bioactivities, cancer, inflammation, delivery

Citation: Zhou J, Xie X, Tang H, Peng C and Peng F (2022) The bioactivities of sclareol: A mini review. Front. Pharmacol. 13:1014105. doi: 10.3389/fphar.2022.1014105

Received: 08 August 2022; Accepted: 14 September 2022;
Published: 03 October 2022.

Edited by:

Hina Siddiqui, University of Karachi, Pakistan

Copyright © 2022 Zhou, Xie, Tang, Peng and Peng. This is an open-access article distributed under the terms of the Creative Commons Attribution License (CC BY). The use, distribution or reproduction in other forums is permitted, provided the original author(s) and the copyright owner(s) are credited and that the original publication in this journal is cited, in accordance with accepted academic practice. No use, distribution or reproduction is permitted which does not comply with these terms.

*Correspondence: Cheng Peng, pengchengchengdu@126.com; Fu Peng, pengf@scu.edu.cn

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