Protective effects of three selected standardized medicinal plant extracts used in Sri Lankan traditional medicine in adriamycin induced nephrotoxic Wistar rats

Exploring the Role of Phenolic Compounds in Chronic Kidney Disease: A Systematic Review

Chronic kidney disease (CKD) presents a formidable global health concern, affecting one in six adults over 25. This review explores the potential of phenolic compounds in managing CKD and its complications. By examining the existing research, we highlight their diverse biological activities and potential to combat CKD-related issues. We analyze the nutritional benefits, bioavailability, and safety profile of these compounds. While the clinical evidence is promising, preclinical studies offer valuable insights into underlying mechanisms, optimal dosages, and potential side effects. Further research is crucial to validate the therapeutic efficacy of phenolic compounds for CKD. We advocate for continued exploration of their innovative applications in food, pharmaceuticals, and nutraceuticals. This review aims to catalyze the scientific community's efforts to leverage phenolic compounds against CKD-related challenges.

Barleria prionitis L. extracts ameliorate doxorubicin-induced acute kidney injury via modulation of oxidative stress, inflammation, and apoptosis

Background and aim

Doxorubicin (DOX) is a chemotherapeutic drug with potential nephrotoxic effects on patients who are on cancer chemotherapy. An interest has been observed in using natural products to ameliorate the potential side effects of DOX. The present study is to investigate the cellular mechanisms underlying the protective effects of Barleria prionitis L. (BP) (Acanthaceae) extracts, DOX-induced acute kidney injury (AKI).

Experimental procedure

Hexane (25 mg/kg/day), ethyl acetate (80 mg/kg/day), n-butanol (70 mg/kg/day), and water (120 mg/kg/day) extracts of BP, were administered to DOX-induced (5 mg/kg (2500 μL/kg), ip) Wistar rats for four consecutive weeks. At the end of the study, investigations were carried out for the assessment of biomarkers of nephrotoxicity, oxidative stress, inflammation, and apoptosis.

Results

Treatments with BP extracts significantly reversed DOX-induced elevations in serum and urine biochemical markers of nephrotoxicity (serum creatinine; 21-33%, blood urea nitrogen; 26-58%, β2-microglobulin; 19-22% and urine total protein; 47-67%). There was a reduction in the levels of tumor necrosis factor-α, interleukin-1β, and malondialdehyde in kidney homogenates of rats treated with the n-butanol extract (by 43, 62, and 24%) and water extract (by 57%, 85%, and 26%) (p < 0.05). Immunohistochemical expression of the pro-apoptotic B-cell associated X protein was reduced while the anti-apoptotic B-cell lymphoma gene product 2 protein was increased in kidney tissues after the treatments with BP extracts.

Conclusions

The selected BP extracts significantly ameliorated DOX-induced AKI. The findings would open new vistas for the development of a drug using the BP extracts to minimize DOX-induced AKI in cancer patients.

Beneficial effects of procyanidin B2 on adriamycin-induced nephrotic syndrome mice: the multi-action mechanism for ameliorating glomerular permselectivity injury

Despite considerable advances in prevention, diagnosis, and therapy, nephrotic syndrome (NS) remains a significant cause of high morbidity and mortality globally. As a result, there is an urgent need to identify novel effective preventative and therapeutic agents for NS. NS is implicated in glomerular permselectivity injury, which can be attributed to oxidative distress, inflammation, lipid nephrotoxicity, podocyte apoptosis, autophagy dysfunction, and slit diaphragm (SLD) dysfunction. In addition to its well-documented antioxidant potency, procyanidin B2 (PB2) may exhibit pleiotropic effects by targeting various canonical signaling events, such as NF-κB, PPARs, PI3K/Akt, mTOR, and the caspase family. As a result, PB2 may be a promising therapeutic target against NS. To test this hypothesis, we established an Adriamycin (ADR)-induced NS mouse model to evaluate the pleiotropic renoprotective effects of PB2 on NS. Here, we demonstrated that PB2 improves podocyte injury via inhibition of NOX4/ROS and Hsp90/NF-κB to exhibit antioxidant and anti-inflammatory potency, respectively. We also show that PB2 indirectly activates the PI3K/Akt axis by regulating SLD protein levels, resulting in normalized podocyte apoptosis and autophagy function. Further, loss of albumin (ALB) induces lipid nephrotoxicity, which we found to be alleviated by PB2 via activation of PPARα/β-mediated lipid homeostasis and the cholesterol efflux axis. Interestingly, our results also suggested that PB2 reduces electrolyte abnormalities and edema. In addition, PB2 may contribute protective effects against trace element dys-homeostasis, which, through alleviating serum ALB loss, leads to a protective effect on glomerular permselectivity injury. Taken together, our results reveal that the identified mechanisms of PB2 on NS are multifactorial and involve inhibition of oxidative distress and inflammatory responses, as well as improvements in podocyte apoptosis and autophagy dysfunction, amelioration of lipid nephrotoxicity, and modulation of electrolyte abnormalities and edema. Thus, we provide a theoretical basis for the clinical application of PB2 against NS.

Nephroprotective mechanisms of Ambrette (Abelmoschus moschatus Medik.) leaf extracts in adriamycin mediated acute kidney injury model of Wistar rats

ETHNOPHARMACOLOGICAL RELEVANCE

Ambrette (Abelmoschus moschatus Medik., Family: Malvaceae) is a common Ayurvedic herbal medicine used in the treatment of kidney-related diseases, in the forms of tea, medicated oil, medicated wine, etc., however, its nephroprotective mechanisms remain unexploited.

AIM OF THE STUDY

To investigate the mechanisms by which the hexane (A-HE), ethyl acetate (A-EE), butanol (A-BE), and aqueous (A-WE) leaf extracts of Ambrette protect against the adriamycin-mediated acute kidney injury in Wistar rats.

MATERIALS AND METHODS

A-HE, A-EE, A-BE, A-WE, and fosinopril sodium were administered at therapeutically effective doses (55, 75, 60, 140, 0.09 mg/kg) to adriamycin-induced (5 mg/kg, ip) Wistar rats for 28 consecutive days.

RESULTS

Oral administration of the selected extracts of A. moschatus resulted in amelioration of kidney injury as observed by the significant changes of biomarkers of kidney function in serum and in urine, biochemical parameters of oxidative stress, and inflammation in kidney homogenates (p < 0.05). Furthermore, the administration of plant extracts caused a significant reduction in total kidney injury scores in H and E stained kidney sections (p < 0.05). The immunohistochemical expression of the inflammatory marker, COX-2, and the pro-apoptotic marker, Bax, were attenuated and the expression of the anti-apoptotic marker, BCL-2, was increased. A-HE exerted superior nephroprotective effects over the other three extracts and the drug reference standard.

CONCLUSIONS

The findings revealed that Ambrette exerts promising protective effects against adriamycin-mediated acute kidney injury through antioxidant, anti-inflammatory, and anti-apoptosis pathways. A-HE might serve as a potential candidate for the development of therapeutic drug leads that will be beneficial in the treatment of acute kidney injury.

Asparagus falcatus L. (Asparagaceae) leaf extracts attenuate doxorubicin-induced renal toxicity via antioxidant, anti-inflammatory, and anti-apoptotic pathways

The search for therapeutic agents that improve kidney function against doxorubicin-induced renal toxicity is important. Herein, the potential nephroprotective activity by Asparagus falcatus L. (AF, Asparagaceae) leaf extracts against doxorubicin-induced renal toxicity (5 mg/kg, ip) in Wistar rats (n = 6/group) after oral administration of hexane (55 mg/kg), ethyl acetate (35 mg/kg), butanol (75 mg/kg), and aqueous (200 mg/kg) extracts of AF for 28 consecutive days was investigated. It was noticed that the treatment with the selected extracts of AF significantly attenuated doxorubicin-induced elevations of serum creatinine, urea nitrogen, β₂-microglobulin, cystatin C, and proteinuria in experimental rats. The histology showed attenuation of the features of acute tubular injury. Treatment regimens significantly reversed the doxorubicin-induced reduction in total antioxidant status, glutathione peroxidase, and glutathione reductase activity in renal tissue homogenates. A suppression in lipid peroxidation was noted with hexane, ethyl acetate, and butanol extracts of AF. Moreover, a reduction in the concentration of the pro-inflammatory mediator TNF-α (p < 0.05), and immunohistochemical expression of COX-2 were observed. The immunohistochemical expression of pro-apoptotic Bax protein was decreased and the anti-apoptotic BCL-2 was increased in renal tissues following the treatments. In conclusion, it was revealed that, hexane, ethyl acetate, butanol, and aqueous extracts of AF attenuate doxorubicin-induced renal toxicity in Wistar rats through antioxidant, anti-inflammatory, and anti-apoptotic pathways. The plant, AF could be recommended as a promising therapeutic agent to minimize renal toxicity induced by doxorubicin in cancer patients, however, subsequent clinical trials are warranted.

Role of autophagy and evaluation the effects of microRNAs 214, 132, 34c and prorenin receptor in a rat model of focal segmental glomerulosclerosis

AIMS

Focal segmental glomerulosclerosis (FSGS) is the common cause of chronic renal disease worldwide. Although there are many etiologic factors which have common theme of podocyte injury conclusive etiology is not clearly understood. In this study, we aimed to explore the role of autophagy in the pathogenesis of podocyte injury, which is the key point in disease progression, and the roles of intrarenal microRNAs and the prorenin receptor (PRR) in the 5/6 nephrectomy and adriamycin nephropathy models of FSGS.

MAIN METHODS

For experimental FSGS model, 5/6 nephrectomy and adriamycin nephropathy models were created and characterized in adult Sprague Dawley rats. Microarray analysis was performed on FSGS and control groups that was confirmed by q-RT-PCR. Beclin1, LC3B, PRR, ATG7 and ATG5 expression were evaluated by western blotting and immunohistochemistry. Also, Beclin1 and PRR expression were measured by ELISA. Glomerular podocyte isolation was performed and autophagic activity was evaluated in podocytes before and after transfection with miRNA mimic and antagonists.

KEY FINDINGS

Glomerular expression of Beclin1, LC3B, PRR, ATG7 and ATG5 were significantly lower in the 5/6 nephrectomy than adriamycin nephropathy group and in both groups lower when compared to control groups. Western blot results were consistent with immunohistochemical data. Electron microscopy revealed signs of impaired autophagy in FSGS. Autophagic activity decreased significantly after miR-214, miR-132 and miR-34c mimics and increased after transfection with antagonists.

SIGNIFICANCE

These results showed that the role of autophagic activity and decreased expression of PRR in FSGS pathogenesis and miR-34c, miR-132 and miR-214 could be a potential treatment strategy by regulating autophagy.

Nephroprotective activity of Vetiveria zizanioides (L.) Nash supplement in doxorubicin-induced nephrotoxicity model of Wistar rats

The nephroprotective effect of standardized aqueous root extract of Vetiveria zizanioides (L.) Nash (Family: Poaceae) was investigated in doxorubicin-induced (20 mg/kg, ip) experimental nephrotoxicity model of Wistar rats. The freeze-dried aqueous refluxed (4 hr) root extract of V. zizanioides (25, 50; equivalent human therapeutic dose and 100 mg/kg) was administered separately to nephrotoxic Wistar rats (n = 6/group). Supplement of V. zizanioides resulted a dose-dependent reduction in raised serum creatinine, β₂ -microglobulin, and blood urea nitrogen and a subsequent increase in serum total protein and albumin in nephrotoxic rats (p < .05). An attenuation of the doxorubicin-induced features of renal parenchymal injury was observed on H- and E-stained sections of the kidney tissues. Nootkatone, dehydroaromadendrene, isokhusenic acid, α-vetivone, and isolongifolene were identified in the methanol extract of V. zizanioides based on the GC-MS chromatogram analysis. The findings revealed that the supplement of standardized aqueous root extract of V. zizanioides had a significant dose-dependent nephroprotective activity against doxorubicin-induced experimental nephrotoxicity. PRACTICAL APPLICATIONS: Vetiveria zizanioides is a medicinal plant with a variety of therapeutic applications in kidney-related diseases. Apparently, it is used as a food ingredient due to its fresh and elegant scent and potential bioactivities. The aqueous root extract of V. zizanioides exerted relatively high antioxidant potential in vitro, substantiating the health effects of the plant pertaining to kidney diseases as a potential source of dietary antioxidant. The administration of the plant extract resulted in significant nephroprotection against doxorubicin-induced experimental nephrotoxicity revealing the significance of V. zizanioides as a promising dietary supplement in the management of kidney disease.