Eucalyptus torquata L. flowers: a comprehensive study reporting their metabolites profiling and anti-gouty arthritis potential.

Gouty arthritis is one of the most common metabolic disorders affecting people. Plant based drugs can lower the risk of this health disorder. The anti-gouty potential of Eucalyptus torquata flowers methanol extract (ETME) was evaluated in vitro via measuring the inhibitory effects of five pro-inflammatory enzymes; xanthine oxidase (XO), hyaluronidase, lipoxygenase (5-LOX), cyclooxygenases COX-1, and COX-2, in addition to evaluating the inhibition of histamine release, albumin denaturation, membrane stabilization, tyrosinase, and protease inhibitory activities. Also, its antioxidant potential was determined using 2,2-diphenyl-1-picrylhydrazyl (DPPH), 2,2'-Azino-bis(3-ethylbenzothiazoline-6-sulfonic acid (ABTS) radical scavenging assays and ferric reducing power assay (FRAP). HPLC-PDA-MS/MS was used to identify the metabolites in the tested extract. The latter exhibited substantial anti-arthritic properties in all assays with comparable potential to the corresponding reference drugs. HPLC-MS/MS analysis of this bioactive extract tentatively annotated 46 metabolites including phloroglucinols, gallic and ellagic acids derivatives, terpenes, flavonoids, fatty acids, and miscellaneous metabolites. Our study highlights the medicinal importance of E. torquata as an anti-gouty candidate and opens new avenues of gouty management.

Euclea divinorum Hiern: Chemical Profiling of the Leaf Extract and Its Antioxidant Activity In Silico, In Vitro and in Caenorhabditis elegans Model.

Euclea divinorum Hiern is a medicinal plant widely distributed in the northeast parts of South Africa. This plant has been used to treat miscarriage and to alleviate gastrointestinal problems. It can also be used externally for the treatment of ulcers and gonorrhea. In this study, we investigated the phytochemical composition of E. divinorum leaf extract using LC-MS and explored its antioxidant properties in vitro and in vivo. The total polyphenolic content of the extract was determined by the Folin-Ciocalteu method. DPPH and FRAP assays were employed to confirm the plant's antioxidant potential in vitro. A survival assay in the Caenorhabditis elegans model was used to evaluate the extract's ability to counteract juglone-induced oxidative stress. Moreover, a docking study was performed for the extract's metabolites, in order to predict possible molecular targets that could explain the antioxidant effect of the plant on a molecular level. This in silico approach was accomplished on three different proteins; xanthine oxidase enzyme, heat shock protein 90 (Hsp90), and induced nitric oxide synthase (iNOS). Docking scores of the resulting poses and their interactions with binding sites' residues were explored for each protein and were compared to those of simultaneously docked respective co-crystallized and reference substrates. The extract furnished promising antioxidant activities in vitro and in vivo in the C. elegans model that might be attributed to the presence of 46 compounds, which showed several interactions and low binding scores with the tested enzymes. In conclusion, E. divinorum is a promising, safe, and effective antioxidant candidate that could be used to ameliorate oxidative stress-related disorders.

Vasorelaxant Effects of Syzygium samarangense (Blume) Merr. and L.M.Perry Extract Are Mediated by NO/cGMP Pathway in Isolated Rat Thoracic Aorta.

Syzygium samarangense (Blume) Merr. and L.M.Perry is utilized widely in traditional medicine. We have reported previously a wide array of pharmacological properties of its leaf extract, among them anti-inflammatory, antioxidant, hepatoprotective, antidiabetic, antiulcer, and antitrypanosomal activities. We also annotated its chemical composition using LC-MS/MS. Here, we continue our investigations and evaluate the vasorelaxant effects of the leaf extract on aortic rings isolated from rats and explore the possible underlying mechanisms. S. samarangense extract induced a concentration dependent relaxation of the phenylephrine-precontracted aorta in the rat model. However, this effect disappeared upon removing the functional endothelium. Pretreating the aortic tissues either with propranolol or NG-nitro-L-arginine methyl ester inhibited the relaxation induced by the extract; however, atropine did not affect the extract-induced vasodilation. Meanwhile, adenylate cyclase inhibitor, MDL; specific guanylate cyclase inhibitor, ODQ; high extracellular KCl; and indomethacin as cyclooxygenase inhibitor inhibited the extract-induced vasodilation. On the other hand, incubation of S. samarangense extract with aortae sections having their intact endothelium pre-constricted using phenylephrine or KCl in media free of Ca2+ showed no effect on the constriction of the aortae vessels induced by Ca2+. Taken together, the present study suggests that S. samarangense extract dilates isolated aortic rings via endothelium-dependent nitric oxide (NO)/cGMP signaling. The observed biological effects could be attributed to its rich secondary metabolites. The specific mechanisms of the active ingredients of S. samarangense extract await further investigations.

Black pepper oil (Piper nigrum L.) mitigates dexamethasone induced pancreatic damage via modulation of oxidative and nitrosative stress.

Dexamethasone acts as an immunosuppressive drug and has been used recently in the management of specific coronavirus disease 2019 (COVID-19) cases; however, various adverse effects could limit its use. In this work, we studied the mitigation effects of black pepper oil (BP oil) on glycemic parameters, dyslipidemia, oxidative and nitrosative stress and pancreatic fibrosis in dexamethasone-treated rats. Animals were divided into five groups that were treated with vehicle, dexamethasone (10 mg/kg, SC) or black pepper oil (BP oil, 0.5 mL, or 1 mL/kg) or metformin (50 mg/kg) plus dexamethasone for 4 consecutive days. Serum insulin, blood glucose, total cholesterol, triglycerides, and Homeostatic Model Assessment for Insulin Resistance (HOMA-IR) were higher in the dexamethasone group vs the control group and decreased in BP oil and metformin groups relative to the dexamethasone group. Pancreatic nitric oxide, inducible nitric oxide synthase and malondialdehyde levels were increased in the dexamethasone group vs the control group and decreased in BP oil and metformin groups relative to the dexamethasone group. Pancreatic endothelial nitric oxide synthase and reduced glutathione were declined in the dexamethasone group vs the control group. They were increased in BP oil and metformin groups relative to the dexamethasone group. Moreover, the pancreatic islets diameter and collagen deposition were assessed and found to be higher in the dexamethasone group vs the control group. BP oil and metformin groups showed to regress this effect. In conclusion, BP oil may alleviate hyperglycemia, hyperinsulinemia, insulin resistance, dyslipidemia and pancreatic structural derangements and fibrosis by suppressing oxidative stress, increasing endogenous antioxidant levels, modulating nitric oxide signaling, preventing pancreatic stellate cells transition and collagen deposition.

Antioxidant and anti-aging effects of Warburgia salutaris bark aqueous extract: Evidences from in silico, in vitro and in vivo studies.

ETHNOPHARMACOLOGICAL RELEVANCE: The genus Warburgia (family Canellaceae) is widely distributed over Afrotropical and Neotropical realms. Traditionally, W. salutaris (G. Bertol.) Chiov., and other Warburgia species are used as anti-inflammatory, antimalarial, antimicrobial, and for wound healing, and treating several skin complaints as well. Specifically, different extracts from W. salutaris were reported to possess diuretic, anti-inflammatory, and cytotoxic effects. AIM OF THE STUDY: This work aimed to investigate the phytochemical composition of an aqueous extract from W. salutaris bark, and evaluate its antioxidant and anti-aging activities in silico, in vitro, and in vivo. MATERIALS AND METHODS: HPLC-PDA-MS/MS was used to investigate the phytochemical components of the extract. The antioxidant potential of the extract was evaluated in vitro using DPPH and FRAP assays. The Caenorhabditis elegans nematodes model was adopted to investigate the antioxidant and the anti-aging effects in vivo by determining the worms' survival rate, level of ROS, HSP16 expression, and nuclear translocation of the transcription factor DAF16. Molecular operating environment (MOE) software was utilized for in silico molecular docking of the extract's components into different enzymes involved in the aging process. Anti-collagenase, anti-elastase, anti-tyrosinase, and anti-hyaluronidase assays were used to evaluate the anti-aging effects in vitro. RESULTS: HPLC-MS analysis furnished 30 compounds, among them catechin, 11α-hydroxy muzigadiolide, mukaadial, pereniporin B, and 11α-hydroxycinnamosmolide. The major components of the extract showed appropriate fitting in the binding site of the target enzymes adopted in the study with considerable minimum free binding energy relative to the standard inhibitors. The extract showed substantial in vitro antioxidant activity in DPPH and FRAP assays and in vitro anti-aging assays against collagenase, elastase, tyrosinase, and hyaluronidase with comparable IC50 values to the reference standards. Moreover, it attenuated oxidative stress in vivo as it significantly increased the survival rate of ROS stressed C. elegans worms, decreased intracellular ROS, decreased the juglone-induced HSP16 expression and enhanced the nuclear localization of DAF16 in a dose-dependent manner. CONCLUSION: Our results support the traditional use of W. salutaris to counteract inflammation and oxidative stress associated with several pathological conditions. In addition, W. salutaris bark extract can be considered as a substantial source for bioactive metabolites with strong potential as anti-aging and antioxidant agents.

Thymus fontanesii attenuates CCl4-induced oxidative stress and inflammation in mild liver fibrosis.

Liver injury is a major public health problem all over the world that raises the demand of developing novel effective and safe remedies. Traditionally, Thyme (Thymus fontanesii) has a therapeutic potential against different organs toxicity due to its antioxidant activity. The present study aimed to evaluate the antioxidant activities in vitro and the possible hepato-protective effects of T. fontanesii aqueous extract (TFAE) against CCl4 induced liver damage (mild fibrosis) in male albino mice and annotate its phytochemical constituents as well. The extract displayed substantial antioxidant activities in vitro and high content of flavonoids and other phenolic compounds. Oral administration of TFAE (especially high dose) significantly suppressed (but with different degrees) the incidence and severity of CCl4 liver toxicity by activating the hepatic antioxidant defense mechanisms, modulating hepatic functions, and decreasing the production of lipid peroxidation, pro-inflammatory mediators, and pro-fibrotic proteins expression including COL1A1, Fn, and TGF-ß1. These activities might be attributed to the presence of 58 secondary metabolites (identified by LC-MS), mainly phenolic acids, flavonoids and diterpenoids that were able, according to molecular docking, to bind to the inhibitor's binding site of three protein targets involved in liver inflammation and fibrosis. These results showcase the antioxidant and anti-inflammatory properties of Thyme (Thymus fontanesii), illustrate the protective and beneficial effects of the plant against CCl4-induced hepatic toxicity in mice, and support its consumption, traditional uses and promotes its valorization as nutraceutical product.

A Leaf Extract of Harrisonia abyssinica Ameliorates Neurobehavioral, Histological and Biochemical Changes in the Hippocampus of Rats with Aluminum Chloride-Induced Alzheimer's Disease.

Aluminum (Al) is an omnipresent mineral element in the environment. The brain is a central target of Al toxicity, being highly susceptible to oxidative damage. Therefore, recognition of drugs or natural products that guard against Al-mediated neuronal cell death is a powerful strategy for prevention and treatment of neurodegenerative disorders. This work aimed to explore the potential of a leaf extract from Harrisonia abyssinica to modulate the neurobehavioral, biochemical and histopathological activities induced experimentally by Al in vivo. Rats subjected to Al treatment displayed a reduction in learning and memory performance in a passive avoidance test accompanied by a decrease in the hippocampal monoamine and glutamate levels in addition to suppression of Bcl2 expression. Moreover, malondialdehyde (MDA), inflammatory markers (TNF-α, IL-1ß), apoptotic markers (caspase-3 and expression of Bax) and extracellular regulated kinase (ERK1/2) levels were elevated along with acetylcholinesterase (AChE) activity, histological changes and marked deposition of amyloid ß plaques in the hippocampus region of the brain tissues being observed in Al-treated animals. Concomitant administration of the high dose of H. abyssinica (200 mg/kg b.w.) restored nearly normal levels of all parameters measured, rather than the low dose (100 mg/kg b.w.), an effect that was comparable to the reference drug (rivastigmine). Molecular docking revealed the appropriate potential of the extract components to block the active site of AChE and ERK2. In conclusion, H. abyssinica leaf extract conferred neuroprotection against Al-induced neurotoxic effects, most likely due to its high phenolic and flavonoid content.

Syzygium samarangense leaf extract mitigates indomethacin-induced gastropathy via the NF-κB signaling pathway in rats.

We previously profiled the chemical composition of wax apple, Syzygium samarangense, leaf extract using HR-LC-MS/MS and reported its antioxidant, hepatoprotective and antitrypanosomal activities. The plant is widely used in traditional medicine to cure several ailments like bronchitis, asthma, diabetes, fever, pathogenic infections, gut spasms, as well as renal diseases. However, neither the gastroprotective effects nor the underlying mechanisms were explored. Here, we investigated the gastroprotective potential of the leaf extract on indomethacin-induced gastric ulcer in rats and explored the involved mechanism(s) of action. Administration of indomethacin significantly increased the ulcer index, mucosal injury, the gastric levels of the inflammatory markers nuclear factor kabba B-p65(NF-κB p65), myeloperoxidase (MPO), interleukin-6 (IL-6), tumor necrosis factor alpha (TNF-α), lipid peroxidation product, malondialdehyde (MDA) and Caspase-3 expression. It reduced the gastric levels of the endogenous antioxidants glutathione as well peroxidase (GPx), reduced glutathione (GSH) and the gastric mucosal protective factors, mucus secretion and goblet cells. Pretreatment with the leaf extract displayed a prominent decrease in the ulcer index, inflammatory cell infiltration, inflammatory markers, MDA, protein expression of Caspase-3 and a significant increase in the gastric levels of the endogenous antioxidants, mucus content and goblet cell proliferation when compared to the indomethacin group. The individual secondary metabolites of the extract exhibited low binding energy when docked into the prostaglandin receptors EP3 and EP4. This study revealed the gastroprotective effect of S. samarangense on indomethacin-induced gastric ulcer in rats. The gastroprotective effects might be attributed to cytoprotective, antioxidant, anti-inflammatory and antiapoptotic activities with a possible potential of activating EP3 and EP4 receptors. In conclusion, S. samarangense has a promising potential in the prevention of NSAIDs-induced ulcers.

Eugenia uniflora and Syzygium samarangense extracts exhibit anti-trypanosomal activity: Evidence from in-silico molecular modelling, in vitro, and in vivo studies.

The parasite Trypanosoma brucei is the main cause of the sleeping sickness threatening millions of populations in many African countries. The parasitic infection is currently managed by some synthetic medications, most of them suffer limited activity spectrum and/or serious adverse effects. Some studies have pointed out the promising therapeutic potential of the plant extracts rich in polyphenols to curb down parasitic infections caused by T. brucei and other trypanosomes. In this work, the main components dominating Eugenia uniflora and Syzygium samarangense plant extracts were virtually screened, through docking, as inhibitors of seven T. brucei enzymes validated as potential drug targets. The in vitro and in vivo anti-T. brucei activities of the extracts in two treatment doses were evaluated. Moreover, the extract effects on the packed cell volume level, liver, and kidney functions were assessed. Five compounds showed strong docking and minimal binding energy to five target enzymes simultaneously and three other compounds were able to bind strongly to at least four of the target enzymes. These compounds represent lead hits to develop novel trypanocidal agents of natural origin. Both extracts showed moderate in vitro anti-trypanosomal activity. Infected animal groups treated over 5 days with the studied extracts showed an appreciable in vivo anti-trypanosomal activity and ameliorated in a dose dependent manner the anaemia, liver, and kidney damages induced by the infection. In conclusion, Eugenia uniflora and Syzygium samarangense could serve as appealing sources to treat trypanosomes infections.

A Polyphenol-Rich Extract From Entada abyssinica Reduces Oxidative Damage in Cryopreserved Ram Semen.

The Splinter bean, Entada abyssinica, is widely used in folk medicine. In the current work, we profiled the secondary metabolites from E. abyssinica bark extract using LC-MS and investigated its effect on cryopreserved ram semen. Twenty-eight compounds, including tannins and gallic acid derivatives that prevailed in the extract, were tentatively identified. Results showed that the quality of the post-thawed semen showed a significant improvement when the extract was added to the extender at a concentration of 375 µg/mL. The progressive motility and plasma membrane integrity of sperm cells were significantly increased in the post-thawed semen; however, the total antioxidant capacity (TAC) was insignificantly increased. A significant decrease in the concentration of hydrogen peroxide was detected as well. No significant changes were observed in activities of lactate dehydrogenase (LDH), alanine aminotransaminase (ALT), and aspartate transaminase (AST) within the treated samples. Intact sperm percentage was significantly increased, while apoptotic and necrotic sperm percentages were reduced significantly. Molecular docking of some individual components from the extract revealed their potential to interfere with the apoptosis cascade in which Bcl-2 is involved. In conclusion, Entada abyssinica appears to be useful for cryopreservation presumably owing to its polyphenol content that has potent antioxidant capacity scavenging reactive oxygen species (ROS), enhancing the endogenous antioxidant system and inhibiting lipid peroxidation.

A Polyphenols-Rich Extract from Moricandia sinaica Boiss. Exhibits Analgesic, Anti-Inflammatory and Antipyretic Activities In Vivo.

In this study, the aerial parts of Moricandia sinaica were evaluated for their in vivo analgesic, anti-inflammatory and antipyretic activities. The analgesic activities were examined using acetic acid-induced writhing, the hot plate test and the tail flick method. The anti-inflammatory and the antipyretic activities were evaluated using carrageenan-induced paw edema in rats and brewer's yeast-induced pyrexia in mice, respectively. The aqueous fraction of the methanol extract (MS-3) showed to be the most bioactive among the other investigated fractions. At the dose of 500 mg/kg, the fraction (MS-3) showed a significant percentage inhibition of the carrageenan-induced edema by 52.4% (p < 0.05). In addition, MS-3 exhibited a significant inhibition of acetic acid-induced writhes by 44.4% and 61.5% (p < 0.001) at 250-mg/kg and 500-mg/kg doses, respectively. At 120 min post-treatment, the rat groups treated with MS-3 displayed statistically significant reduction in rectal temperature (p < 0.001) by 1.7 °C and 2.2 °C at 250- and 500-mg/kg doses, respectively. The phytochemical composition of the fraction (MS-3) was characterized by high-performance liquid chromatography-mass spectrometry (HPLC-PDA-MS/MS). Molecular docking studies demonstrated that the polyphenols identified in MS-3 revealed good binding energy upon docking to some target proteins involved in pain response and inflammation, such as the cannabinoid receptors CB1 and CB2, the fatty acid amide hydrolase (FAAH) and the cyclooxygenase COX-1 and COX-2 enzymes. Based on the findings from the present work, it could be concluded that the aerial parts extract of M. sinaica exerts potential analgesic, anti-inflammatory and antipyretic effects in rats.

Thymus algeriensis and Thymus fontanesii: Chemical Composition, In Vivo Antiinflammatory, Pain Killing and Antipyretic Activities: A Comprehensive Comparison.

This study aimed to investigate the chemical composition, and evaluate the antioxidant, anti-inflammatory, anti-pyretic, and the analgesic properties of methanol extracts from the leaves of Thymus algeriensis and Thymus fontanesii (Lamiaceae). Thirty-five secondary metabolites were characterized in both extracts using HPLC-PDA-ESI-MS/MS. Phenolic acids, mainly rosmarinic acid and its derivatives, dominated the T. algeriensis extract, while the phenolic diterpene carnosol and the methylated flavonoid salvigenin, prevailed in T. fontanesii extract. Molecular docking study was carried out to estimate the anti-inflammatory potential and the binding affinities of some individual secondary metabolites from both extracts to the main enzymes involved in the inflammation pathway. In vitro enzyme inhibitory assays and in vivo assays were used to investigate the antioxidant and anti-inflammatory activities of the extracts. Results revealed that both studied Thymus species exhibited antioxidant, anti-inflammatory, analgesic, and antipyretic effects. They showed to be a more potent antioxidant than ascorbic acid and more selective against cyclooxygenase (COX-2) than diclofenac and indomethacin. Relatively, the T. fontanesii extract was more potent as COX-2 inhibitor than T. algeriensis. In conclusion, Thymus algeriensis and Thymus fontanesii may be interesting candidates for the treatment of inflammation and oxidative stress-related disorders.

Haematoxylon campechianum Extract Ameliorates Neuropathic Pain via Inhibition of NF-κB/TNF-α/NOX/iNOS Signalling Pathway in a Rat Model of Chronic Constriction Injury.

: In this study, the phytochemical composition and the possible prophylactic effects of an aqueous ethanol extract of Haematoxylon campechianum flowers (HCF) on peripheral neuropathic pain in a chronic constriction injury (CCI) rat model are investigated. Rats with induced CCI were subjected to neuropathic pain behaviour tests and evaluated by chemical, thermal, and mechanical sensation tests and functional recovery of the brain stem and sciatic nerve at 7- and 14-day intervals. The effect of the extract on acute pain and inflammation is also investigated. The extract exerted both peripheral and central analgesic and anti-inflammatory properties in addition to antipyretic effects that are clear from targeting COX, LOX and PGE. It was found that CCI produced significant thermal and mechanical hyperalgesia, cold allodynia and deleterious structural changes in both sciatic nerve and brain stem. Treatments with HCF extract significantly improved cold and thermal withdrawal latency, mechanical sensibility and ameliorated deleterious changes of sciatic nerve and brain stem at different dose levels. The extract also ameliorated oxidative stress and inflammatory markers in brain stem and sciatic nerve. It suppressed the apoptotic marker, p53, and restored myelin sheath integrity. The effects of HCF extract were more potent than pregabalin. Fifteen secondary metabolites, mainly gallotannins and flavonoids, were characterized in the extract based on their retention times and MS/MS data. The identified phenolic constituents from the extract could be promising candidates to treat neuropathic pain due to their diverse biological activities, including antioxidant, anti-inflammatory and neuroprotective properties.

Salix tetrasperma Roxb. Extract Alleviates Neuropathic Pain in Rats via Modulation of the NF-κB/TNF-α/NOX/iNOS Pathway.

Patients with neuropathic pain experience chronic painful tingling, burning, and prickling sensations accompanied with hyperalgesia and/or allodynia. In this study, 38 secondary metabolites of a methanol extract from Salix tetrasperma flowers were identified by liquid chromatography-mass spectrometry (HPLC-MS/MS). The extract showed substantial anti-inflammatory, central and peripheral anti-nociceptive, antipyretic, and antioxidant activities in vitro and in different animal models. In the chronic constriction injury (CCI) rat model, the extract was able to attenuate and significantly relieve hyperalgesia and allodynia responses in a dose dependent manner and restore the myelin sheath integrity and Schwann cells average number in the sciatic nerve. The enzyme-linked immunosorbent assay (ELISA) showed that the extract significantly reduced the expression of various pro-inflammatory biomarkers including nuclear factor kabba B (NF-κB), tumor necrosis factor alpha (TNF-α), prostaglandin E2 (PGE2), 5-lipoxygenase (5-LOX), cyclooxygenase-2 (COX-2), inducible nitric oxide synthase (iNOS), and the oxidative stress biomarker NADPH oxidase 1 (NOX1), in brain stem and sciatic nerve tissues. These findings were supported by in vitro enzyme inhibition assays (COX-1, COX-2 and 5-LOX). Moreover, the extract significantly reduced p53 expression in the brain stem tissue. These findings support the use of S. tetrasperma in folk medicine to alleviate pain. It could be a promising natural product for further clinical investigations to treat inflammation, nociceptive pain and chronic neuropathic pain.

Chemical profiling of secondary metabolites of Eugenia uniflora and their antioxidant, anti-inflammatory, pain killing and anti-diabetic activities: A comprehensive approach.

ETHNOPHARMACOLOGICAL RELEVANCE: The red Brazilian cherry, Eugenia uniflora, is widely used in traditional medicine. The aim of this study was to investigate the phytochemical composition of a methanol extract from leaves of E. uniflora and characterization of the isolated compounds. In addition, we aimed to determine the antioxidant activities in vitro and in a cell-based (HaCaT cell) model. We also studied the anti-inflammatory, analgesic, antipyretic and antidiabetic activities in relevant rat models. The molecular mode of action of the antidiabetic activities was also investigated. MATERIALS AND METHODS: UV, MS, and NMR (1H, 13C, DEPT, COSY, HMQC, and HMBC) were used to identify the secondary metabolites. Antioxidant effects were determined in vitro and in HaCaT cells. The ani-inflammatory and antidibetic activities were studied in experimental animals. RESULTS: In this work, a new compound, gallic acid 3-O-[6'-O-acetyl-ß-D-glucoside], along with 16 known plant secondary metabolites (PSM) were isolated, characterized using UV, MS, and NMR (1H, 13C, DEPT, COSY, HMQC, and HMBC). Noticeable antioxidant effects were determined in HaCaT cells: The extract reduced the elevated levels of ROS and p38 phosphorylation and increased the reduced glutathione (GSH) content induced by UVA. The extract showed substantial anti-inflammatory activities in vivo: It diminished the edema thickness in carrageenan-induced hind-paw edema rat model and lowered the leukocyte migration into the peritoneal cavity. In rats, central and peripheral anti-nociceptive properties were also observed: The extract reduced the number of writhing in acid induced writhing and increased the latency time in hot plate test. Furthermore, adequate antipyretic effects were observed: The extract reduced the elevated rectal temperature in rats after intraperitoneal injection of Brewer's yeast. Moreover, the extract possessed robust anti-diabetic activity in streptozotocin (STZ) -diabetic rats: It markedly reduced the elevated serum glucose and lipid peroxidation levels and increased the insulin concentration in serum with higher potency than the positive control, glibenclamide. These effects might be associated with the interaction of PSM with the conserved amino acid residues of human pancreatic α-amylase (HPA), maltase glucoamylase (MGAM-C) and aldose reductase (ALR2) revealing considerable binding affinities. CONCLUSION: A plethora of substantial pharmacological properties indicates that Eugenia uniflora is a good antioxidant and a sustainable by-product with solid therapeutic potential for treating diabetes, inflammation, pain and related oxidative stress diseases.

Albizia anthelmintica: HPLC-MS/MS profiling and in vivo anti-inflammatory, pain killing and antipyretic activities of its leaf extract.

In the current work, the phytochemical composition of a leaf methanol extract from Albizia anthelmintica was thoroughly investigated. The antioxidant, anti-inflammatory, analgesic, and antipyretic activities of the extract were investigated. In the carrageenan induced hind paw edema bioassay; the extract significantly reduced the edema thickness in rats and diminished the leukocyte migration to the peritoneal cavity in mice. The extract exhibited central and peripheral anti-nociceptive effects; it significantly decreased the number of acetic acid induced writhes and prolonged the latency time in the hot plate test. The extract showed a substantial antipyretic activity as it decreased significantly the elevated rectal temperature in mice after intraperitoneal injection of Brewer's yeast. Molecular docking of some major compounds in the extract to COX-1, COX-2 and 5-LOX, enzymes involved in the inflammation cascade, revealed appreciable interactions with the conserved amino acid residues in these target proteins. These findings were confirmed with in vitro enzyme inhibitory assays in which the extract showed IC50 values of 4.11, 0.054, and 1.74 µg/mL towards COX-1, COX-2 and 5-LOX, respectively. The extract displayed solid antioxidant properties as well with a TAC value of 35.13 U/L and EC50of 5.36 µg/mL in DPPH assay. These findings suggested that Albizia anthelmintica is a good antioxidant with potential therapeutic efficacy for treating inflammation, pain and related oxidative stress disorders.

Chemical composition, antioxidant and hepatoprotective activities of methanol extracts from leaves of Terminalia bellirica and Terminalia sericea (Combretaceae).

BACKGROUND: Plants belonging to the genus Terminalia such as Terminalia bellirica and Terminalia sericea are used traditionally to treat several diseases and health disorders. Up to this date, the roots of Terminalia sericea and the fruits of Terminalia bellirica are the mostly studied plant parts. The phytochemical composition and the biological activities of the leaves of both species are not well identified so far. METHODS: The secondary metabolites of Terminalia bellirica and Terminalia sericea leaves were identified using HPLC-PDA-MS/MS. The antioxidant activities of the leaves extracts were determined by DPPH and FRAP assays. The hepatoprotective potential was evaluated in rats with D-galactosamine induced liver damage. The effect of the extracts on the expression of the anti-apoptotic marker Bcl-2 was measured in an immunohistochemical study. The most abundant compounds identified in the studied extracts were docked into Bcl-2: Bim (BH3) interaction surface using molecular operating environment software. RESULTS: A total of 85 secondary metabolites were identified in the leaf extracts of both species. Ellagitannins such as corilagin, chebulagic acid, galloylpunicalagin, and digalloyl-hexahydroxydiphenoyl-hexoside were found to be the major components in Terminalia bellirica whereas flavonoid glycosides including quercetin rutinoside and quercetin galloyl-glucoside were highly abundant in Terminalia sericea. The studied extracts exhibited pronounced antioxidant activities, moderate anti-apoptotic and hepatoprotective potential. In silico docking experiments revealed that the compounds abundant in the extracts were able to bind to Bcl-2: Bim (BH3) interaction surface with an appreciable binding free energy. DISCUSSION: The antioxidant and hepatoprotective activities exhibited by the studied extracts might be attributed to the high content of the polyphenols. The anti-apoptotic activity could be due to the interference with the apoptotic pathway mediated by Bcl-2: Bim interaction. These findings support the medicinal relevance of Terminalia bellirica and Terminalia sericea and provide a rational base for their utilization in folk medicine.

Tannin-rich extracts from Lannea stuhlmannii and Lannea humilis (Anacardiaceae) exhibit hepatoprotective activities in vivo via enhancement of the anti-apoptotic protein Bcl-2.

The potential hepatoprotective activities of two Lannea species were explored in vivo. Furthermore, the binding activities of their main polyphenols to the antiapoptotic protein Bcl-2 were investigated. Based on HPLC-MS/MS results, 22 secondary metabolites were characterized in L. stuhlmannii (mainly tannins), while 20 secondary metabolites (mainly sulphated tannins) were identified in L. humilis. Both extracts exhibited substantial antioxidant activities in vitro and counteracted D-galactosamine induced intoxication in rats in vivo and increased the total antioxidant capacity (TAC) of liver tissues. In addition to reducing the elevated levels of AST and total bilirubin, both extracts significantly attenuated the deleterious histopathologic changes in liver after D-galactosamine-intoxication. Also, both extracts protected hepatocytes from apoptotic cell death and increased the expression of the anti-apoptotic protein Bcl-2. The identified compounds from both extracts can bind to the Bcl-2: Bim (BH3) interface with an appreciable binding free energy. Hydrogen and ionic bonds and hydrophobic interactions with amino acid residues in the hydrophobic face of Bim (BH3) domain were discovered. To sum up, L. humilis and L. stuhlmanni exhibited promising hepatoprotective activities in vivo against D-GalN-induced liver injury and their hepatoprotection is due to the antioxidant and anti-apoptotic effects of tannins and proanthocyanidins.

A proanthocyanidin-rich extract from Cassia abbreviata exhibits antioxidant and hepatoprotective activities in vivo.

ETHNOPHARMACOLOGICAL RELEVANCE: Cassia abbreviata is a small to medium sized branched umbrella-shaped deciduous tree. It is widely spread in the tropics, especially in Africa, having a long history in traditional medicine for the treatment of numerous conditions such as headaches, diarrhea, constipation, some skin diseases, malaria, syphilis, pneumonia, stomach troubles, uterine pains, and against gonorrhea. AIM OF THE STUDY: We investigated the phytochemical constituents of a root extract from Cassia abbreviata using HPLC-PDA-ESI-MS/MS. We also determined the antioxidant activities in vitro and in vivo using the nematode Caenorhabditis elegans as a model organism. The hepatoprotective activities in case of D-galactosamine (D-GaIN)-induced hepatotoxicity were studied in a rat model. MATERIALS AND METHODS: HPLC-PDA-ESI-MS/MS analysis allowed the identification of the secondary metabolites of the methanol extract. DPPH and FRAP assays were used to determine the antioxidant activities in vitro. Using the C. elegans model, survival rates under juglone induced oxidative stress, intracellular ROS content, quantification of Phsp-16.2: GFP expression and subcellular DAF-16: GFP localization were investigated to determine the antioxidant activities in vivo. The in vivo hepatoprotective potential of the root extract was evaluated for D-galactosamine (D-GaIN)-induced hepatotoxicity in rats. The activity of the liver enzymes alanine aminotransferase (ALT), aspartate aminotransferase (AST) and gamma-glutamyltransferase (GGT), in addition to liver peroxidation product malondialdehyde (MDA) and glutathione content (GSH), as well as albumin and total bilirubin concentration, were determined. A histopathological study was also performed. RESULTS AND CONCLUSIONS: C. abbreviata root extract is rich in polyphenolics, particularly proanthocyanidins. HPLC-PDA-ESI-MS/MS analysis resulted in the identification of 57 compounds on the bases of their mass spectra. (epi)-Catechin, (epi)-afzelechin, (epi)-guibourtinidol, and (ent)-cassiaflavan monomers as well as their dimers, trimers, and their diastereomers are the main components of the extract. The total phenolic content amounted for 474mg/g root extract expressed as gallic acid equivalent using the Folin-Ciocalteu method. The extract exhibited powerful antioxidant activity with EC50 of 6.3µg/mL in DPPH and 19.15mM FeSO4 equivalent/mg sample in FRAP assay. In C. elegans model, the extract (200µg/mL) was able to increase the survival rate by 44.56% and reduced the ROS level to 61.73%, compared to control group. Pretreatment of rats with 100mg extract/kg (b. wt.) reduced MDA by 47.36% and elevated GSH by 59.1%. The extract caused a significant reduction of ALT, AST and GGT activities by 11%, 35.7% and 65%, respectively. The findings of this study suggest that the proanthocyanidin-rich extract from C. abbreviata may be an interesting candidate for hepatoprotective activity in case of hepatocellular injury.

Hepatoprotective and hypoglycemic effects of a tannin rich extract from Ximenia americana var. caffra root.

BACKGROUND: Liver diseases and diabetes are serious health disorders associated with oxidative stress and ageing. Some plant polyphenols can lower the risk of these diseases. PURPOSE: We investigated the phytochemical profiling of a root extract from Ximenia americana var. caffra using HPLC-PDA-ESI-MS/MS. The antioxidant activities in vitro were investigated. The hepatoprotective activities were studied in rat models with d-galactosamine (d-GaIN)-induced hepatotoxicity and the antidiabetic activities in STZ-diabetic rats were also investigated. MATERIALS AND METHODS: HPLC-PDA-ESI-MS/MS was used to identify plant phenolics. The antioxidant activities in vitro were determined using DPPH and FRAP assays. The in vivo hepatoprotective activities were determined for d-GaIN-induced hepatotoxicity in rats. We determined the liver markers alanine aminotransferase (ALT), aspartate aminotransferase (AST) and gamma-glutamyltransferase (GGT), liver peroxidation product malondialdehyde (MDA), glutathione content (GSH), albumin and total bilirubin concentration. The histopathological changes in rat liver were also studied. The antidiabetic activities were also investigated in STZ-diabetic rats and serum glucose, serum insulin hormone, and lipid peroxides were determined. RESULTS: The root extract is rich in tannins with 20 compounds including a series of stereoisomers of (epi)catechin, (epi)catechin-(epi)catechin, (epi)catechin-(epi)catechin-(epi)catechin, and their galloyl esters. Promising antioxidant potential was observed in vitro in DPPH assay with EC50 of 6.5 µg extract / 26 µg raw material and in FRAP assay with 19.54 mM FeSO4 compared with ascorbic acid (EC50 of 2.92 µg/ml) and quercetin (FeSO4 24.04 mM/mg), respectively. Significant reduction of serologic enzymatic markers and hepatic oxidative stress markers such as ALT, AST, MDA, GGT, and total bilirubin, as well as elevation of GSH and albumin were observed in rats with d-galactosamine-induced liver damage treated with the extract. These findings agree with a histopathological examination suggesting a hepatoprotective potential for the root extract. The root extract can mediate an antidiabetic effect by reducing elevated blood glucose and serum lipid peroxides levels and by increasing insulin in STZ-diabetic rats by -107, -31.1, +11.3%, respectively. CONCLUSIONS: The results of this study suggest that the tannin-rich extract from Ximenia americana var. caffra could be an interesting candidate for the treatment of several health disorders associated with oxidative stress such as hepatocellular injury and diabetes.