Modulatory potential of α-amyrin against hepatic oxidative stress through antioxidant status in Wistar albino rats

In Vitro Anti-Toxoplasma Activity of Extracts Obtained from Tabebuia rosea and Tabebuia chrysantha: The Role of β-Amyrin

Toxoplasmosis is a parasitic disease caused by the protozoan Toxoplasma gondii that is highly prevalent worldwide. Although the infection is asymptomatic in immunocompetent individuals, it severely affects immunocompromised individuals, causing conditions such as encephalitis, myocarditis, or pneumonitis. The limited therapeutic efficacy of drugs currently used to treat toxoplasmosis has prompted the search for new therapeutic alternatives. The aim of this study was to determine the anti-Toxoplasma activity of extracts obtained from two species of the genus Tabebuia. Twenty-six extracts, 12 obtained from Tabebuia chrysantha and 14 from Tabebuia rosea, were evaluated by a colorimetric technique using the RH strain of T. gondii that expresses β-galactosidase. Additionally, the activity of the promising extracts and their active compounds was evaluated by flow cytometry. β-amyrin was isolated from the chloroform extract obtained from the leaves of T. rosea and displayed important anti-Toxoplasma activity. The results show that natural products are an important source of new molecules with considerable biological and/or pharmacological activity.

Chiranthodendron pentadactylon Larreat (Sterculiaceae), a Potential Nephroprotector against Oxidative Damage Provoked by STZ-Induced Hyperglycemia in Rats

BACKGROUND

Chiranthodendron pentadactylon, known in Mexico as the "tree of the little hands", flower's infusion is used to treat kidney failure associated with diseases such as diabetes. The aim of this work is to evaluate the antioxidant effect of the methanolic extract of its flowers on oxidative damage in kidneys caused by streptozotocin in rats.

METHODS

The extract phytochemical profile was performed with HPLC. Antioxidant potential in vitro was determined with DPPH and total phenolic tests; antioxidant evaluation in vivo was performed in diabetic rats administered daily via the intragastric route (100 and 200 mg/kg) for 6 weeks; serum glucose/creatinine, food/water consumption, and urinary volume were measured. Relative weight, protein/DNA ratios and oxidative stress were measured in renal tissue.

RESULTS

The extract showed 20.53% of total phenolic content and IC50 of 18.05 µg/mL in DPPH, and this was associated with ferulic acid, phloretin and α-amyrin. Both doses showed a moderate decrease in the protein/DNA ratio in renal tissue, and the same behavior was observed for total urinary protein loss and serum creatinine, while the best antioxidant effect was exerted by a lower dose, which increased catalase activity and decreased lipid peroxidation in the kidneys.

CONCLUSIONS

Results demonstrated that C. pentadactylon methanolic flower's extract improves renal function through antioxidant mechanisms during experimental diabetes.

Promising hepatoprotective agents from the natural sources: a study of scientific evidence

Background

Natural bioactive components derived from plant secondary metabolites have been pronounced as valuable alternatives for anticipating and subsiding hepatotoxic effects and its chronic complications based on experimental verification. The focus of this review is to elucidate the commonly used modern medicine for the treatment of liver disease and how major phytoconstituents have been tested for hepatoprotective activity, mechanism of action of some promising agents from natural sources, and clinical trial data for treating in patients with different liver diseases by the aid of natural phytoconstituents.

Main text

The review shows fifteen major isolated phytoconstituents, their biological sources, chemical structures, utilized plant parts, type of extracts used, hepatoprotective assay method, and their possible mechanism of action on the hepatoprotection. Nine promising hepatoprotective leads from natural sources with their chemistry and hepatoprotective mechanism are mentioned briefly. The review further includes the recent clinical trial studies of some hepatoprotective leads and their clinical outcome with different liver disease patients. Scientific studies revealed that antioxidant properties are the central mechanism for the phytoconstituents to subside different disease pathways by upsurging antioxidant defense system of cells, scavenging free radicals, down surging lipid peroxidation, improving anti-inflammatory potential, and further protecting the hepatic cell injury. In this review, we summarize recent development of natural product-based hepatoprotective leads and their curative potential for various sort of liver diseases. Furthermore, the usefulness of hit and lead molecules from natural sources for significant clinical benefit to discover new drug molecule and downsizing the problems of medication and chemical-induced hepatotoxic effects is extrapolated.

Conclusion

Further research are encouraged to elucidate the pharmacological principle of these natural-based chemical agents which will stimulate future pharmaceutical development of therapeutically beneficial hepatoprotective regimens.

Shea Nut Oil Extracts Enhance the Intra-Articular Sodium Hyaluronate Effectiveness on Surgically Induced OA Progression in Rats

Osteoarthritis (OA) progression is associated with joint pain and stiffness. Intra-articular hyaluronic acid (IAHA) injection in knee OA restores the viscoelasticity of the joint and prevents cartilage damage. Shea nut oil extract (SNO) was shown to provide chondroprotection on surgically-induced OA progression in rats. Here we aim to examine IAHA injection supplemented with SNO diet for a synergetic evaluation on the disease progression in OA rats. We employed an anterior cruciate ligament transection plus medial meniscectomy-induced knee OA rat model with up to 12 weeks of sign/behavior observation (knee width, weight-bearing) and histological assessments of joint damage. We found both IAHA and SNO alone significantly attenuated histological changes of cartilage degeneration and synovial reactions in these knee OA rats. Nonetheless, oral SNO alone mitigated OA pain and inflammation while IAHA alone had no significant impact on the weight-bearing test and knee joint swelling. Moreover, with IAHA-treated rats fed with oral SNO diet, additional anti-inflammatory and anti-nociceptive effects were found, which further enhanced and maintained IAHA protection. Given the differential phenotype of oral SNO vs. IAHA, a regimen of IAHA coupled with SNO supplement provides a long-term effect of IAHA treatment. Taken together, the SNO supplement can be safely used as an adjuvant diet for chronic symptomatic relief of OA coupled with IAHA management.

The hepatoprotective activities of Kalimeris indica ethanol extract against liver injury in vivo

Kalimeris indica (L.) Sch. Bip. is a traditional Chinese medicine (TCM) and a portion of food used for cooking in China. It has been demonstrated that an ethanol extract of K. indica has an anti-inflammatory effect by inhibition of nitric oxide (NO) production on murine macrophage RAW264.7 cells after lipopolysaccharide (LPS) induction. In this study, the hepatoprotective effects of the total phenolics of K. indica (TPK), the total triterpenes of K. indica (TTK), and the total flavones of K. indica (TFK) from ethanol extracts of K. indica were evaluated in Bacille Calmette-Guerin (BCG)/LPS-induced liver injury in vivo. The treatments of TPK, TTK, and TFK improved liver injury in mice. Additionally, all treatments significantly not only reduced the hepatic malondialdehyde (MDA) content and hepatic total nitric oxide synthase (tNOS) but also induced the hepatic superoxide dismutase (SOD) and glutathione peroxidase (GSH-Px) activity. The treatments of TPK and TTK significantly reduced the hepatic inducible nitric oxide synthase (iNOS). The treatments of TPK, TTK, and TFK reduced the serum total bilirubin (T-Bil), and only TFK treatment reduced the serum alanine aminotransferase (ALT). Our results suggest that TPK, TTK, and TFK from ethanol extracts of K. indica might play an essential protective role against BCG/LPS-induced liver injury in vivo.

In Vivo Pharmacological and Anti-inflammatory Evaluation of Xerophyte Plantago sempervirens Crantz

Known for centuries throughout the world, Plantago species have long been used as traditional herbal remedies for many diseases related to inflammatory conditions of the skin, respiratory and digestive tract, or even malignancy. This study is aimed first at investigating the in vitro antioxidant and regenerative effects of Plantago sempervirens Crantz hydroalcoholic extract followed by an in vivo experiment using a turpentine oil-induced inflammation model. The in vitro evaluation for antioxidant activity was performed using classical assays such as DPPH and TEAC scavenging assays but also EPR, and the total phenolic content was determined using the Folin-Ciocalteu reagent. The wound healing assay was performed on human cells (Human EA.hy926). Besides, the prooxidant activity was determined using a method which involves in situ free radical generation by laccase and the oxidation of haemoglobin. On turpentine oil-induced inflammation in rats, the in vivo effects of three doses of P. sempervirens extracts (100%, 50%, and 25%) were assessed by measuring oxidative stress (MDA, TOS, OSI, NO, CAT, and SOD) and inflammatory (CRP, WBC, and NEU) parameters. Having a rich polyphenolic content, the xerophyte P. sempervirens exhibited a strong in vitro antioxidant activity by scavenging radicals, enhancing cell regeneration, and reducing oxidative stress markers. Diluted P. sempervirens extract (25%) exhibited the best antioxidant, wound healing, and anti-inflammatory activity.

Comparative Proteomic Analysis of Liver Steatosis and Fibrosis after Oral Hepatotoxicant Administration in Sprague-Dawley Rats

The past decade has seen an increase in the development and clinical use of biomarkers associated with histological features of liver disease. Here, we conduct a comparative histological and global proteomics analysis to identify coregulated modules of proteins in the progression of hepatic steatosis or fibrosis. We orally administered the reference chemicals bromobenzene (BB) or 4,4'-methylenedianiline (4,4'-MDA) to male Sprague-Dawley rats for either 1 single administration or 5 consecutive daily doses. Livers were preserved for histopathology and global proteomics assessment. Analysis of liver sections confirmed a dose- and time-dependent increase in frequency and severity of histopathological features indicative of lipid accumulation after BB or fibrosis after 4,4'-MDA. BB administration resulted in a dose-dependent increase in the frequency and severity of inflammation and vacuolation. 4,4'-MDA administration resulted in a dose-dependent increase in the frequency and severity of periportal collagen accumulation and inflammation. Pathway analysis identified a time-dependent enrichment of biological processes associated with steatogenic or fibrogenic initiating events, cellular functions, and toxicological states. Differentially expressed protein modules were consistent with the observed histology, placing physiologically linked protein networks into context of the disease process. This study demonstrates the potential for protein modules to provide mechanistic links between initiating events and histopathological outcomes.

Development, Physicochemical Characterization and In Vitro Anti-Inflammatory Activity of Solid Dispersions of α,β Amyrin Isolated from Protium Oilresin

α,β Amyrin (ABAM) is a natural mixture of pentacyclic triterpenes that has shown a variety of pharmacological properties, including anti-inflammatory effect. ABAM is isolated from Burseraceae oilresins, especially from the Protium species, which is commonly found in the Brazilian Amazon. This work aimed to develop solid dispersions (SD) of ABAM with the following hydrophilic polymers: polyvinylpyrrolidone (PVP-K30), polyethylene glycol (PEG-6000) and hydroxypropylmethylcellulose (HPMC). The SDs were prepared by physical mixture (PM), kneading (KND) and rotary evaporation (RE) methods. In order to verify any interaction between ABAM and the hydrophilic polymers, physicochemical characterization was performed by Fourier transform infrared (FTIR), scanning electron microscopy (SEM), powder X-ray diffraction (XRD), thermogravimetry (TG) and differential scanning calorimetry (DSC) analysis. Furthermore, an in vitro anti-inflammatory assay was performed with ABAM alone and as SDs with the hydrophilic polymers. The results from the characterization analysis show that the SDs were able to induce changes in the physicochemical properties of ABAM, which suggests interaction with the polymer matrix. In vitro anti-inflammatory assay showed that the SDs improved the anti-inflammatory activity of ABAM and showed no cytotoxicity. In conclusion, this study showed the potential use of SDs as an efficient tool for improving the stability and anti-inflammatory activity of ABAM without cytotoxicity.

In vitro and in vivo antioxidative and hepatoprotective activity of aqueous extract of Cortex Dictamni

AIM

To investigate the antioxidant and hepatoprotective effects of Cortex Dictamni aqueous extract (CDAE) in carbon tetrachloride (CCl₄)-induced liver damage in rats.

METHODS

The in vitro antioxidant effect of CDAE was investigated using α,α-diphenyl-β-picrylhydrazyl (DPPH), 2,2’-azino-bis (3-ethylbenzthiazoline-6-sulfonic acid) (ABTS), β-carotene bleaching, reducing power, and thiobarbituric acid reactive substance assays. A linoleic acid system, including ferric thiocyanate (FTC) and thiobarbituric acid (TBA) assays, was used to evaluate the inhibition of lipid peroxidation. The in vivo hepatoprotective and antioxidant effects of CDAE against CCl₄-induced liver damage were evaluated in Sprague-Dawley rats. Silymarin was used as a positive control. Liver damage was assessed by determining hepatic histopathology and liver marker enzymes in serum. Enzyme and non-enzyme antioxidant levels and lipid peroxide content were measured in the liver. Cytochrome P450 2E1 (CYP2E1) protein expression was measured via immunohistochemical staining. Nuclear factor E2-related factor (Nrf2), heme oxygenase-1 (HO-1), NAD(P)H quinine oxidoreductase 1 (NQO1), and γ-glutamylcysteine synthetase catalytic subunit (γ-GCSc) protein expression was measured by Western blot.

RESULTS

Our results showed that CDAE exhibited a strong antioxidant activity in vitro. CDAE scavenged DPPH and ABTS radicals in a dose-dependent manner. CDAE inhibited lipid peroxidation with a lipid peroxide inhibition rate of 40.6% ± 5.2%. In the FTC and TBA assays, CDAE significantly inhibited lipid peroxidation (P < 0.01). In vivo histopathological studies indicated that CCl₄-induced liver injury was alleviated following CDAE treatment in rats of both sexes. CDAE (160 and 320 mg/kg) significantly prevented CCl₄-induced elevations of alkaline phosphatase, glutamate pyruvate transaminase, aspartate aminotransferase, and total bilirubin levels in rats of both sexes (P < 0.05, 0.01, or 0.001). Moreover, CDAE restored the decreased activities of hepatic antioxidant enzymes, including superoxide dismutase, catalase, and glutathione peroxidase, as well as non-enzyme antioxidant glutathione, which were induced by CCl₄ treatment. CDAE significantly suppressed the up-regulation of CYP2E1 and promoted Nrf2, HO-1, NQO1, and γ-GCSc protein expression.

CONCLUSION

CDAE exhibits good antioxidant performance in vitro, with marked radical-scavenging and anti-lipid peroxidation activities. CDAE is effective in preventing CCl₄-induced hepatic damage in rats of both sexes. The hepatoprotective activity of CDAE may be attributable to its antioxidant activity, which may involve Keap1-Nrf2-mediated antioxidant regulation.

Profile of bioactive compounds in Nymphaea alba L. leaves growing in Egypt: hepatoprotective, antioxidant and anti-inflammatory activity

Background

Nymphaea alba L. represents an interesting field of study. Flowers have antioxidant and hepatoprotective effects, rhizomes constituents showed cytotoxic activity against liver cell carcinoma, while several Nymphaea species have been reported for their hepatoprotective effects. Leaves of N. alba have not been studied before. Therefore, in this study, in-depth characterization of the leaf phytoconstituents as well as its antioxidant and hepatoprotective activities have been performed where N. alba leaf extract was evaluated as a possible therapeutic alternative in hepatic disorders.

Methods

The aqueous ethanolic extract (AEE, 70%) was investigated for its polyphenolic content identified by high-resolution electrospray ionisation mass spectrometry (HRESI-MS/MS), while the petroleum ether fraction was saponified, and the lipid profile was analysed using gas liquid chromatography (GLC) analysis and compared with reference standards. The hepatoprotective activity of two doses of the extract (100 and 200 mg/kg; P.O.) for 5 days was evaluated against CCl₄-induced hepatotoxicity in male Wistar albino rats, in comparison with silymarin. Liver function tests; aspartate aminotransferase (AST), alanine aminotransferase (ALT), alkaline phosphatase (ALP), gamma glutamyl transpeptidase (GGT) and total bilirubin were performed. Oxidative stress parameters; malondialdehyde (MDA), reduced glutathione (GSH), catalase (CAT), superoxide dismutase (SOD), total antioxidant capacity (TAC) as well as inflammatory mediator; tumour necrosis factor (TNF)-α were detected in the liver homogenate. Histopathological examination of the liver and immunohistochemical staining of caspase-3 were performed

Results

Fifty-three compounds were tentatively identified for the first time in N.alba leaf extract, where ellagitannins represent the main identified constituents. Nine hydrocarbons, two sterols and eleven fatty acids were identified in the petroleum ether extract where, palmitic acid and linolenic acids represented the major saturated and unsaturated fatty acid respectively. N.alba AEE significantly improved the liver function, oxidative stress parameters as well as TNF-α in addition to the amelioration of histopathological features of the liver and a profound decrease in caspase-3 expression.

Conclusion

These results shed light on the hepatoprotective effect of N. alba that is comparable with that of silymarin. The antioxidant activities of N. alba extract in addition to the inhibition of crucial inflammatory mediator, as TNF-α, might be the possible hepatoprotective mechanisms.

α-Amyrin attenuates high fructose diet-induced metabolic syndrome in rats

This study investigated the effect of α-amyrin (a pentacyclic triterpene) on high-fructose diet (HFD)-induced metabolic syndrome in rats. Male Wistar rats were randomly distributed into different groups. The control group was fed normal rat chow diet. The HFD group was fed HFD (60%; w/w) for 42 days. Pioglitazone (10 mg/kg, orally, once daily) was used as a standard drug. α-Amyrin was administered in 3 doses (50, 100, and 200 mg/kg, orally, once daily along with HFD). Plasma glucose, total cholesterol, triglycerides, and high-density lipoprotein cholesterol (HDL-C) were estimated. Changes in blood pressure, oral glucose tolerance, and insulin tolerance were measured. Hepatic oxidative stress as well as messenger RNA (mRNA) and protein levels of peroxisome proliferator-activated receptor alpha (PPAR-α) were analyzed. A significant increase in systolic blood pressure, plasma glucose, total cholesterol, and plasma triglycerides and a significant decrease in HDL-C were observed in HFD rats as compared with control rats. Glucose tolerance and insulin tolerance were also significantly impaired with HFD. α-Amyrin prevented these changes in a dose-dependent manner. Hepatic oxidative stress as well as micro- and macrovesicular fatty changes in hepatocytes caused by HFD were also attenuated by α-amyrin. α-Amyrin preserved the hepatic mRNA and protein levels of PPAR-α, which was reduced in HFD group. This study thus demonstrates that α-amyrin attenuates HFD-induced metabolic syndrome in rats.

Chronic Kidney Disease Induced Intestinal Mucosal Barrier Damage Associated with Intestinal Oxidative Stress Injury

Background. To investigate whether intestinal mucosal barrier was damaged or not in chronic kidney disease progression and the status of oxidative stress. Methods. Rats were randomized into two groups: a control group and a uremia group. The uremia rat model was induced by 5/6 kidney resection. In postoperative weeks (POW) 4, 6, 8, and 10, eight rats were randomly selected from each group to prepare samples for assessing systemic inflammation, intestinal mucosal barrier changes, and the status of intestinal oxidative stress. Results. The uremia group presented an increase trend over time in the serum tumor necrosis factor-alpha, interleukin-6 (IL-6) and IL-10, serum D-lactate and diamine oxidase, and intestinal permeability, and these biomarkers were significantly higher than those in control group in POW 8 and/or 10. Chiu's scores in uremia group were also increased over time, especially in POW 8 and 10. Furthermore, the intestinal malondialdehyde, superoxide dismutase, and glutathione peroxidase levels were significantly higher in uremia group when compared with those in control group in POW 8 and/or 10. Conclusions. The advanced chronic kidney disease could induce intestinal mucosal barrier damage and further lead to systemic inflammation. The underlying mechanism may be associated with the intestinal oxidative stress injury.

Tangeretin Alleviates Cisplatin-Induced Acute Hepatic Injury in Rats: Targeting MAPKs and Apoptosis

Despite its broad applications, cisplatin affords considerable nephro- and hepatotoxicity through triggering inflammatory and oxidative stress cascades. The aim of the current investigation was to study the possible protective effects of tangeretin on cisplatin-induced hepatotoxicity. The impact of tangeretin on cisplatin-evoked hepatic dysfunction and histopathologic changes along with oxidative stress, inflammatory and apoptotic biomarkers were investigated compared to silymarin. Tangeretin pre-treatment significantly improved liver function tests (ALT and AST), inhibited cisplatin-induced lipid profile aberrations (total cholesterol and triglycerides) and diminished histopathologic structural damage in liver tissues. Tangeretin also attenuated cisplatin-induced hepatic inflammatory events as indicated by suppression of tumor necrosis factor-α (TNF-α) and enhancement of interleukin-10 (IL-10). Meanwhile, it lowered malondialdehyde (MDA), nitric oxide (NO) and nuclear factor erythroid 2-related factor 2 (NRF-2) levels with restoration of glutathione (GSH), and glutathione peroxidase (GPx). Regarding mitogen-activated protein kinase (MAPK) pathway, tangeretin attenuated cisplatin-induced increase in phospho-p38, phospho-c-Jun N-terminal kinase (p-JNK) and phospho-extracellular signal-regulated kinase (p-ERK1/2) in liver tissues. In addition, tangeretin downregulated Bax expression with augmentation of Bcl-2 promoting liver cell survival. Our results highlight the protective effects of tangeretin against cisplatin-induced acute hepatic injury via the concerted modulation of inflammation, oxidative stress, MAPKs and apoptotic pathways.