Immunosuppressive and hepatoprotective potential of Sarcococca saligna and its biomarker components

Sarcococca species: A source of bioactive steroidal alkaloids - A review

BACKGROUND

Sarcococca species (the family Buxaceae), containing a large number of steroidal alkaloids, were often used as medicinal plants for treating various ailments, such as fever, pain, and inflammation.

OBJECTIVE

The current study aims to highlight the natural observation and pharmacological actions of Sarcococca steroidal alkaloids and related compounds.

METHODS

Scientific literature of phytochemical studies and pharmacological examinations of Sarcococca species were collected from four main sources: Google Scholar, Web of Science, PubMed, and journal websites. "Sarcococca" and "steroidal alkaloids" were the primary keywords to search for references. The study covers almost all English publications from the 1960 s to the present. ChemDraw Ultra 12.0 was used to draw chemical structures of phytochemicals.

RESULTS

Phytochemical results indicated that about 170 secondary metabolites have been detected in Sarcococca, of which 144 compounds (84.7%) can be classified as steroidal alkaloids. Other classes included sterols, triterpenoids, flavonoids, and mono-phenols. Sarcococca crude plant extracts, fractions, and their steroidal alkaloid isolates have pharmacological properties, such as cytotoxic, antimicrobial, antioxidative, antiinflammatory, antileishmanial, antiplasmodial, and antidiabetic activities. They were also recorded to protect against harmful conditions to the neurons, liver, and gastrointestinal system, and exert vasorelaxant, analgesic, estrogen biosynthesis, and nematicidal activities. Some steroidal alkaloids are better than the standard drugs to inhibit acetylcholinesterase (AChE) and butyrylcholinesterase (BChE) enzymes. Generally, substituted groups at nitrogenous atoms might be attributed to the differences in pharmacological results.

CONCLUSION

Advances in chromatographic isolations of steroidal alkaloids to obtain huge amounts are necessary. In vivo biological experiences and clinical testing are encouraged.

Hepatoprotective Effect of Annulohypoxylon stygium Melanin on Acute Alcoholic Liver Injury in Mice

Annulohypoxylon stygium melanin (AsM) has various functional properties such as antioxidant and anti-radiation, but its biological activity in vivo has not been fully investigated. In this study, we researched the effects of AsM on the protection against acute liver injury in mice and its mechanism. The results showed that AsM had no significant effect on body weight in mice but reduced the liver index. It was able to significantly decrease the activities of aspartate aminotransferase (AST) and alanine aminotransferase (ALT), the contents of triglyceride (TG) and total cholesterol (TC) in mice. Simultaneously, it raised the levels of superoxide dismutase (SOD), peroxidase (CAT), and glutathione peroxidase (GSH-Px), which obviously exceeded those of the EtOH group. AsM could significantly lower the levels of inflammatory factors, with inhibition rates of 68.30%, 29.0%, and 19.50% for IL-1β, IL-6, and TNF-α, respectively. H&E and Oil red O staining also showed that AsM ameliorated liver damage and lipid accumulation in mice. The protective mechanism of AsM may be associated to the nuclear factor erythroid 2-related factor 2 (Nrf2) antioxidant signaling pathway, which could activate the downstream antioxidant enzymes heme oxygenase-1 (HO-1), glutamate-cysteine ligase modifier subunit (GCLM), and glutamate-cysteine ligase catalytic subunit (GCLC). These findings confirmed that AsM had an alleviating effect on alcoholic liver injury and provided new thoughts for the development of natural product.

Research Progress of Natural Active Substances with Immunosuppressive Activity

The increasing prevalence of autoimmune diseases globally has prompted extensive research and the development of immunosuppressants. Currently, immunosuppressive drugs such as cyclosporine, rapamycin, and tacrolimus have been utilized in clinical practice. However, long-term use of these drugs may lead to a series of adverse effects. Therefore, there is an urgent need to explore novel drug candidates for treating autoimmune diseases. This review aims to find potential candidate molecules for natural immunosuppressive compounds derived from plants, animals, and fungi over the past decade. These compounds include terpenoids, alkaloids, phenolic compounds, flavonoids, and others. Among them, compounds 49, 151, 173, 200, 204, and 247 have excellent activity; their IC50 were less than 1 μM. A total of 109 compounds have good immunosuppressive activity, with IC50 ranging from 1 to 10 μM. These active compounds have high medicinal potential. The names, sources, structures, immunosuppressive activity, and the structure-activity relationship were summarized and analyzed.

Sarcococca saligna fabricated gold nanoparticles alleviated in vitro oxidative stress and inflammation in human adipose-derived stem cells

Oxidative stress is a destructive phenomenon that affects various cell structures including membranes, proteins, lipoproteins, lipids, and DNA. Oxidative stress and inflammation owing to lifestyle changes may lead to serious diseases such as Cancers, Gout, and Arthritis etc. These disorders can be prevented using different therapeutic strategies including nanomedicine. Biosynthesized gold nanoparticles (GNPs) because of their anti-inflammatory and antioxidant bioactivities can be key player in reversal of these ailments. This study was carried out to evaluate the anti-inflammatory and antioxidant potential of bio fabricated GNPs with Sarcococca saligna (S. saligna) extract on injured human adipose-derived Mesenchymal stem cells (hADMSCs). GNPs were characterized by ultraviolet-visible (UV-Vis) spectroscopy, Scanning Electron Microscopy (SEM), x-ray diffraction (XRD), Fourier transform infrared spectroscopy (FTIR), and energy dispersive x-ray (EDS). Phytochemical screening of biosynthesized GNPs exhibited a significant release of polyphenols, that is, total phenolic content (TPC) and total flavonoid content (TFC). GNPs priming amended the in vitro injury caused by Monosodium Iodoacetate (MIA) as exhibited by improved cell viability, wound closure response and superoxide dismutase activity (SOD). The anti-inflammatory conduct assessed through NF-κB pathway and other associated inflammatory markers reported down-regulation of TNF-α (0.644 ± 0.045), IL-1β (0.694 ± 0.147) and IL-6 (0.622 ± 0.112), apoptosis causing genes like Caspase-3 (0.734 ± 0.13) and BAX (0.830 ± 0.12), NF-κB pathway, p65 (0.672 ± 0.084) and p105 (0.539 ± 0.083) associated genes. High SOD activity (95 ± 5.25%) revealed by treated hADMSCs with GNPs also supported the antioxidant role of GNPs in vitro model. This study concludes that S. saligna bio fabricated GNPs priming may improve the therapeutic potential of hADMSCs against chronic inflammatory problems by regulating NF-κB pathway.

Sarcococca saligna extract attenuates formaldehyde-induced arthritis in Wistar rats via modulation of pro-inflammatory and inflammatory biomarkers

Sarcococca saligna plant is commonly used as traditional therapy for arthritis especially in Asian countries. The current study is designed to explore the anti-arthritic potential of S. saligna aqueous methanolic extract (SSME). Preliminary proximate study and HPLC analysis were performed to investigate the phytochemical characterization and quality control. The safety of the SSME was evaluated by performing an acute oral toxicity study (OECD guidelines 425). The anti-arthritic potential of SSME was explored by in vivo formaldehyde-induced arthritis model. The antiarthritic effect of the SSME was determined through paw diameter, arthritic index, body weight, biochemical and haematological parameters. Radiographic and histopathological studies were also carried out to evaluate the results. qRT-PCR was performed to determine the upregulation and downregulation of anti- and pro-inflammatory cytokines in rats while ELISA was done to determine the concentration of HSP-70, IL-6 and TNF-α in the serum. Results of acute oral toxicity showed no abnormality and mortality. There was no noticeable change in haematological and biochemical parameters. Histopathological examination exhibited the normal structure of vital organs. So, SSME might be safe at a 2000 mg/kg dose, proposing that LD₅₀ was higher than 2000 mg/kg body weight. Gallic acid, catechin, hydroxyl benzoic acid, sinapic acid, caffeic acid, ferulic acid and p-cumaric acid were identified by HPLC. The outcomes of in vivo formaldehyde-induced arthritic model showed that SSME significantly reduced paw inflammation and arthritic index and improved haematological and biochemical parameters. Moreover, the SSME influentially down-regulated the gene expression of IL-1β, IL-6, COX-2, PGE2, TNF-α and NF-κB, and up-regulated the expression of IL-4, and IL-10. The results of the undertaken study suggest that S. saligna have strong anti-arthritic activity supporting its conventional application as the remedy of rheumatoid arthritis.

Crystal structure of (1S)-N-(chloromethyl)-1-((4S,6aR,8aS, 8bR,9aR)-4-methoxy-6a,8a-dimethyl-1,3,4, 5,6,6a,6b,7,8,8a,9a,10,10a,10b-tetradecahydro-8bH-naphtho[2′,1′:4,5] indeno[1,2-b]oxiren-8b-yl)-N-methylethan-1-amine, C24H46ClNO5

C24H46ClNO5, orthorhombic, P212121 (no. 19), a = 7.5992(3) Å, b = 9.6634(5) Å, c = 34.7499(7) Å, V = 2551.8(10) Å3, Z = 4, R gt(F) = 0.0554, wR ref(F 2) = 0.1479, T = 170 K.

Evaluation of antidiabetic potential of steroidal alkaloid of Sarcococca saligna

The demand for natural medicines has increased because of their limited adverse effects. The aim of study is to explore the antidiabetic potential of isolated steroidal alkaloid from Sarcococca saligna in streptozotocin induced diabetic rats. To determine the antidiabetic activity of steroidal alkaloids, diabetes was induced in rats by injecting streptozotocin intraperitoneally at a dose of 40 mg/Kg. After a week of STZ injection the treatment were started and the 8th day was considered as the 1st day of treatment and up to four weeks the rats were treated with steroidal alkaloids. Animals were divided into five groups, group 1 considered as a control group by receiving normal saline (1 ml/Kg) twice daily and group 2, 3, 4 were treated with active compound sarcovagine-D, saracodine and holaphylline at the dose of 5 mg/Kg subcutaneously twice a day while group 5 was treated with a standard drug glibenclamide at a dose of 1 mg/Kg/day. The result showed that treated group 2 and 4 reduced the glucose level in blood significantly while group 3 showed moderate glucose reduction. The fructosamine level reduced significantly in treating group 4 from the 2nd week of treatment while group 2 and 3 decreased the level significantly in week 4 in diabetic rats. The treated groups showed gradual decreases the glucose level in 1st and 2nd week of oral glucose tolerance test compared to control group. The group receiving holaphylline (4) and sarcovagine-D (2) showed good improvements in blood lipids while the effect of compound on body weight showed less significant improvement. The present study concluded that steroid alkaloids from isolated Sarcococca saligna possess hypoglycemic effect and improve others diabetes associated complications. Together these finding further research is needed using a range of doses to explore the other possible beneficial effects in diabetes mellitus and its molecular mechanism.

Steroidal Alkaloids as an Emerging Therapeutic Alternative for Investigation of Their Immunosuppressive and Hepatoprotective Potential

The compounds, sarcovagine-D, alkaloid-C, and holaphylline isolated from Sarcococca saligna were found to possess immunosuppressive activities. These compounds were characterized for in vitro inhibition on human T-cells proliferation and IL-2 production. The compounds showed significant immunosuppressive effect on IL-2 production as well as on phytohemagglutinin stimulated T-cell proliferation in a dose dependent manner. Of all the tested compounds holaphylline was found to be less toxic and safe. These compounds were then evaluated for their in vivo hepatoprotective potential against CCl₄, in which alkaloid-C and holaphylline showed markedly reduced liver inflammation and biochemical parameter (ALT, AST, and ALP) of liver injury. The decrease in the activity of hepatic antioxidant enzyme (SOD) was significantly prevented by holaphylline, likewise gradually the levels of MDA and GSH were also normalized compared to silymarin. The CCl₄ induced inflammation and necrosis around the central vein of liver was reduced by sarcovagine-D, alkaloid-C and holaphylline, to 8%, 4% to 1% respectively as assessed by histopathology, thus having better hepatoprotective effect compared to positive control. Steroidal alkaloids attenuated the inflammation of liver around the injured central vein region by down regulating the CCl₄ induced activation of hepatic macrophages as well as their number respectively. Therefore, the in vitro and in vivo results suggest that steroidal alkaloids from S. saligna could be excellent immunosuppressive and hepatoprotective agents.

Hepatoprotective activity of viscosine is mediated by attenuation of hepatic macrophages and iNOS expression in CCl4-intoxicated rats

This study investigated the molecular mechanism(s) of the protective effects of a C-alkylated flavonoid, viscosine on an animal model of CCl₄-induced hepatotoxicity. Viscosine at 20, 50 and 100 mg kg^-1 was orally administered in a dose dependent manner per day for 3 days before the CCl₄ (1 : 1 v/v in olive oil, 1 ml kg^-1) treatment and 2 days after the treatment. Hepatoprotection was assessed in terms of reduction in serum enzyme activities (ALT, AST, and ALP) that occur after CCl₄ injury, and by histopathology and immunohistochemistry. The rise in serum levels of alanine aminotransferase (ALT), aspartate aminotransferase (AST), and alkaline phosphatase (ALP) in CCl₄-intoxicated rats was markedly suppressed by viscosine in a concentration dependent manner. The decrease in the activity of hepatic antioxidant enzyme, SOD, was significantly prevented by viscosine, likewise gradually the levels of MDA and GSH were also normalized compared to silymarin. Viscosine also reduced the CCl₄-induced damaged area from 2% to 0% as assessed by histopathology and prevented the mixed inflammatory infiltrate. Viscosine attenuated the inflammation in the liver around the injured central vein region by downregulating the CCl₄ induced activation of hepatic CD68+ macrophages, thereby reducing their number as well. The expression of inducible nitric oxide synthase (iNOS) was more potentially suppressed by viscosine compared to the FDA approved positive control silymarin. The results of this study indicate that viscosine could be effective in protecting the liver from acute CCl₄-induced injury. The hepatoprotective mechanisms of viscosine may be related to the free radical scavenging and attenuation of oxidative stress, as well as to the inhibition of inflammatory response in the liver. Here, we are proposing a novel mechanism of action of viscosine and suggesting that it may be a safe and better in vivo antioxidant.