Protective effect of dietary polyphenol caffeic acid on ethylene glycol-induced kidney stones in rats

Antiurolithic activity of Zaleya pentandra (L.) C Jeffrey in ethylene glycol-induced calcium oxalate crystal rat model; A scientific validation of traditional use for kidney stone prevention

ETHNOPHARMACOLOGICAL RELEVANCE

Traditional herbal remedies have been used for treating nephrolithiasis, but the relevant scientific evidence is limited. Zaleya pentandra (L.) C. Jeffrey is traditionally used for the prevention of kidney stones in various cultures. However, its efficacy has not been scientifically studied.

AIM OF THE STUDY

This study aimed to investigate the antiurolithic activity of Zaleya pentandra, and validate its traditional used for preventing kidney stones.

MATERIALS AND METHODS

The crude ethanolic extract of Z. pentandra (Zp.Crd) was evaluated through in vitro and in vivo studies. In vitro experiments assessed its impact on crystal count and morphology in metastable calcium oxalate solutions. In vivo studies involved diuretic and ethylene glycol-induced calcium oxalate crystal formation in male Wistar rats.

RESULTS

Zp.Crd transforms calcium oxalate crystals from harmful calcium oxalate monohydrate (COM) to calcium oxalate dihydrate (COD). In vivo, Zp.Crd exhibited dose-dependent (30-300 mg/kg) diuretic activity in rats by significantly increasing urinary sodium (Na+) and potassium (K+) excretion, similar to the standard diuretic hydrochlorothiazide (HCT). In the urolithiasis model, Zp.Crd exhibited dose-dependent antiurolithic effects by reducing kidney crystals and significantly altering lithogenic factors induced by ethylene glycol, including crystalluria, oxaluria, calcium, creatinine, and urea, in the urine and serum of treated rats. Zp.Crd also exhibited antioxidant effects, effectively combating oxidative lithogenic stress in rats.

CONCLUSION

Zp.Crd has been shown to demonstrate antiurolithic activity against CaOx stones through CaOx crystal inhibition, diuretic activity, antioxidant properties, hypocalciuric effects, and hypercitrauric actions. The findings underscore Zp.Crd's potential as a viable alternative or supplemental therapy to current urolithiasis treatments, paving the door for further clinical trials and its inclusion into modern medical practices.

Unlocking New Approaches to Urolithiasis Management Via Nutraceuticals

Urolithiasis, commonly known as kidney stones, is characterized by the formation of hard deposits in the urinary tract. These stones can cause severe pain and discomfort, and their management typically involves a combination of medical interventions and lifestyle modifications. According to the literature, 30% and 50% of urolithiasis cases recur. Between 9 and 12% of persons in industrialised countries are predicted to have urolithiasis at some time. Due to the high frequency of stone formation, recurrent nature, and prevalence in adults, it has a significant impact on society, the person, and the health care system. Adopting the best prophylactic measures is crucial in light of these developments to decrease the impact of urolithiasis on individuals and society. In recent years, there has been growing interest in the potential role of nutraceuticals in the management of urolithiasis. Nutraceuticals, such as herbal extracts, vitamins, minerals, and probiotics, have gained recognition for their potential in promoting urinary health and reducing the risk of urolithiasis. These compounds can aid in various ways, including inhibiting crystal formation, enhancing urine pH balance, reducing urinary calcium excretion, and supporting kidney function. Additionally, nutraceuticals can help alleviate symptoms associated with urolithiasis, such as pain and inflammation. While medical interventions remain crucial, incorporating nutraceuticals into a comprehensive management plan can offer a holistic approach to urolithiasis, improving patient outcomes and quality of life. Therefore, nutraceuticals may be a desirable choice for treating and avoiding recurring urolithiasis for patients and medical professionals. Therefore, the present study has focused on nutraceuticals' role in preventing urolithiasis.

The protective effect of allium cepa against ethylene glycol-induced kidney stones in rats

1Background

Kidney stones is one of the serious medical conditions affecting populations worldwide. So, we aimed in this study to investigate the protective effect of allium cepa administration against KSD.

2Methods

24 adult male albino rats were assigned into 3 groups; group I: control group; group II: received ethylene glycol (EG) in the drinking water for 4 weeks; and group III received EG in the drinking water plus freshly prepared allium cepa extract (ACE) for 4 weeks. Renal function tests and urine analysis were done. Tissue oxidative stress markers (SOD and MDA) were assessed, and kidney expression of SIRT-1, Beclin, LC3, osteopontin, and Regucalcin were measured by RT-qPCR. Histopathological assessment and immunohistochemistry for Bax, Beclin-1 and TNF-α were performed.

3Results

There was a significant improved kidney function tests in the ACE received group compared to EG group (P < 0.001). The present study showed less stones formation and apoptosis with decreased osteopontin and autophagy genes expression in the ACE received group compared to EG group (P < 0.001). While, regucalcin and SIRT-1 genes showed higher expression in the former group than the later group (P < 0.001).

4 Conclusion

Alium Cepa extract administration has a significant protective effect against kidney stones formation.

The Protective Role of Dietary Polyphenols in Urolithiasis: Insights into Antioxidant Effects and Mechanisms of Action

Urolithiasis is a common urological disease with increasing prevalence and high recurrence rates around the world. Numerous studies have indicated reactive oxygen species (ROS) and oxidative stress (OS) were crucial pathogenic factors in stone formation. Dietary polyphenols are a large group of natural antioxidant compounds widely distributed in plant-based foods and beverages. Their diverse health benefits have attracted growing scientific attention in recent decades. Many literatures have reported the effectiveness of dietary polyphenols against stone formation. The antiurolithiatic mechanisms of polyphenols have been explained by their antioxidant potential to scavenge free radicals and ROS, modulate the expression and the activity of endogenous antioxidant and prooxidant enzymes, regulate signaling pathways associated with OS, and maintain cell morphology and function. In this review, we first describe OS and its pathogenic effects in urolithiasis and summarize the classification and sources of dietary polyphenols. Then, we focus on the current evidence defining their antioxidant potential against stone formation and put forward challenges and future perspectives of dietary polyphenols. To conclude, dietary polyphenols offer potential applications in the treatment and prevention of urolithiasis.

Kidney Stone Prevention

Kidney stone disease (KSD) (alternatively nephrolithiasis or urolithiasis) is a global health care problem that affects almost people in developed and developing countries. Its prevalence has been continuously increasing with a high recurrence rate after stone removal. Although effective therapeutic modalities are available, preventive strategies for both new and recurrent stones are required to reduce physical and financial burdens of KSD. To prevent kidney stone formation, its etiology and risk factors should be first considered. Low urine output and dehydration are the common risks of all stone types, whereas hypercalciuria, hyperoxaluria, and hypocitraturia are the major risks of calcium stones. In this article, up-to-date knowledge on strategies (nutrition-based mainly) to prevent KSD is provided. Important roles of fluid intake (2.5-3.0 L/d), diuresis (>2.0-2.5 L/d), lifestyle and habit modifications (for example, maintain normal body mass index, fluid compensation for working in high-temperature environment, and avoid cigarette smoking), and dietary management [for example, sufficient calcium at 1000-1200 mg/d, limit sodium at 2 or 3-5 g/d of sodium chloride (NaCl), limit oxalate-rich foods, avoid vitamin C and vitamin D supplements, limit animal proteins to 0.8-1.0 g/kg body weight/d but increase plant proteins in patients with calcium and uric acid stone and those with hyperuricosuria, increase proportion of citrus fruits, and consider lime powder supplementation] are summarized. Moreover, uses of natural bioactive products (for example, caffeine, epigallocatechin gallate, and diosmin), medications (for example, thiazides, alkaline citrate, other alkalinizing agents, and allopurinol), bacterial eradication, and probiotics are also discussed. Adv Nutr 2023;x:xx-xx.

Oxidized forms of uromodulin promote calcium oxalate crystallization and growth, but not aggregation

Roles of an abundant human urinary protein, uromodulin (UMOD), in kidney stone disease were previously controversial. Recently, we have demonstrated that oxidative modification reverses overall modulatory activity of whole urinary proteins, from inhibition to promotion of calcium oxalate (CaOx) stone-forming processes. We thus hypothesized that oxidation is one of the factors causing those previously controversial UMOD data on stone modulation. Herein, we addressed effects of performic-induced oxidation on CaOx crystal modulatory activity of UMOD. Sequence analyses revealed two EGF-like calcium-binding domains (65th-107th and 108th-149th), two other calcium-binding motifs (65th-92nd and 108th-135th), and three oxalate-binding motifs (199th-207th, 361st-368th and 601st-609th) in UMOD molecule. Analysis of tandem mass spectrometric dataset of whole urinary proteins confirmed marked increases in oxidation, dioxidation and trioxidation of UMOD in the performic-modified urine samples. UMOD was then purified from the normal urine and underwent performic-induced oxidative modification, which was confirmed by Oxyblotting. The oxidized UMOD significantly promoted CaOx crystallization and crystal growth, whereas the unmodified native UMOD inhibited CaOx crystal growth. However, the oxidized UMOD did not affect CaOx crystal aggregation. Therefore, our data indicate that oxidized forms of UMOD promote CaOx crystallization and crystal growth, which are the important processes for CaOx kidney stone formation.

Ursolic acid treats renal tubular epithelial cell damage induced by calcium oxalate monohydrate via inhibiting oxidative stress and inflammation

Ursolic acid (UA) has been proved to have antioxidant and anti-inflammatory effects. However, it is not clear whether it has a protective impact on kidney damage induced by crystals of calcium oxalate monohydrate (COM). This work aimed to make clear the potential mechanism of UA protecting COM-induced kidney damage. The results manifested that high- and low-dose UA reduced COM crystals in COM rats' kidney, down-regulated urea, creatinine, and neutrophil gelatinase-associated lipocalin (NGAL) levels in rat plasma, declined kidney tissue and HK-2 cell apoptosis, inhibited Bax expression but elevated Bcl-2 expression. Additionally, UA alleviated renal fibrosis in COM rats, repressed α-SMA and collagen I protein expressions in the kidney and COM rats' HK-2 cells, depressed COM-induced oxidative damage in vivo and in vitro via up-regulating Nrf2/HO-1 pathway, up-regulated SOD levels and reduced MDA levels, down-regulated TNF-α, IL-1β, and IL-6 levels in vivo and in vitro via suppressing activation of TLR4/NF-κB pathway. In summary, the results of this study suggest that COM-induced renal injury can be effectively improved via UA, providing powerful data support for the development of effective clinical drugs for renal injury in the future.

Litholytic Activities of Natural Bioactive Compounds and Their Mechanism Insights

Urolithiasis is a disease characterized by the formation of stones, which are crystalline accretions that form in the urinary tract from minerals dissolved in the urine. Moreover, it is considered to be a complex and multifactorial disease, requiring treatment. Unfortunately, current treatments are insufficient or may induce several side effects. In fact, medicinal plants are among the anti-litholytic treatments that are strongly recommended by many studies. Indeed, these natural resources contain bioactive molecules of different natures, such as flavonoids, terpenoids, alkaloids, and phenolic acids, which have recently demonstrated very important anti-litholytic effects. The molecular mechanisms involved are multiple and variable, and can reach cellular and molecular levels. In this review, we have discussed in depth the work that has studied the bioactive molecules of medicinal plants and their major potential against urolithiasis. Scientific databases, including Web of Science, PubMed, and Google Scholar, were searched from their inception until April 2021.The cellular and molecular mechanisms are presented and discussed. Some mechanisms of action related to these bioactive compounds are highlighted. This review could provide a scientific starting point for further studies on urolithiasis and natural bioactive compounds, especially flavonoids.

Socio-Cultural Significance of Yerba Maté among Syrian Residents and Diaspora

Socio-Cultural Significance of Yerba Maté among Syrian Residents and Diaspora. Syria is the world's second-largest importer of the dried leaves of Ilex paraguariensis A.St.-Hil., commonly known as yerba maté. The unique story of yerba maté in the Syrian beverage culture started at the beginning of the twentieth century when Syrian migrants returning from South America brought the beverage with them. The overall aim of our study is to understand yerba maté use among Syrians and its role as an essential part of the Syrian beverage culture. We compare yerba maté consumption on spatial, gender, and religious bases through semi-structured interviews with 50 respondents, with equal participation among genders, place of residence, and cultural-religious groups (Sunni, Alawite, Christian, Druze, and Ismaili). We found that the Alawite and Druze groups have the highest yerba maté consumption, and that men drink more than women. Yerba maté was the most preferred stimulant drink among participants, followed by coffee and tea, respectively. Interviews reveal social and cultural factors, perceived addiction, perceived pleasure, and perceived health properties as the drivers behind yerba maté consumption in Syria.

SUPPLEMENTARY INFORMATION

The online version contains supplementary material available at 10.1007/s12231-021-09523-6.

Calculus-related functional protein expression in ureteral calculus-adhered polyp: A preliminary study

To explore the expressions of calculus-related functional proteins in the ureteral calculus-adhered polyp tissues and investigate the role of these proteins in the formation of adhesions between the calculus and polyp.Patients with ureteral calculi and polyps who underwent ureteroscopic lithotripsy for the excision of polyps between January 2019 and June 2019 were enrolled. Polyps obtained from each patient were divided into 2 groups using a matched pairs design: observation group (polyps adhered to calculus) and control group (polyps not adhered to calculus). Histopathological examination of polyps was performed using hematoxylin and eosin staining. Polyp tissues were immunohistochemically stained to assess the expressions of calculus-related functional proteins, that is, annexin A1, calcium-binding protein S100A9 (S100A9), uromodulin, and osteopontin. Furthermore, quantitative analysis was performed using the H-score of tissue staining; Pearson correlation analysis was performed for proteins with high expression.Overall, 40 polyp specimens were collected from 20 patients with ureteral calculi combined with polyps (observation group, 20 specimens; control group, 20 specimens). Hematoxylin and eosin staining revealed obvious epithelial cell proliferation in polyps of both groups; crystals were observed in the epithelial cells of the polyp tissue in the observation group. The expression levels of annexin A1 and S100A9 in the observation group were significantly greater than those in the control group (P < .05). However, no obvious expression of osteopontin or uromodulin was observed in the polyp tissues of both groups. There was a strong correlation between the increased expressions of annexin A1 and S100A9 in the observation group (R = 0.741, P = .022).We documented increased expressions of annexin A1 and S100A9 in the ureteral calculus-adhered polyp tissues. Annexin A1 and S100A9 may play an essential role in the adhesion of calculus and polyp and the growth of calculi.

Amelioration of lithiatic injury to renal tissue by candesartan and sodium thiosulfate in a rat model of nephrolithiasis

AIM

Nephrolithiasis is a chronic metabolic condition affecting 10% of population worldwide. The present study aimed to investigate the possible protective role of candesartan (CAND) and sodium thiosulfate (STS) in ameliorating ethylene glycol (EG) induced nephrolithiasis.

METHODS

One hundred male Wistar rats were divided into five groups: Normal control group, nephrolithiasis (EG) group (1% EG in drinking water), Cystone (CYS) group (EG + 750 mg/kg CYS, orally, once daily), STS group (EG + 0.4 gm/kg STS, intraperitoneally, 3 times/week) and CAND group (EG + 70 μg/mL CAND in drinking water). Treatments and EG administration commenced on the same day and continued for 28 days. CYS was used as reference drug. Urine, blood, and renal tissues were collected at the end of the experiment for assessment of kidney function tests (serum creatinine and urea), urinary (8-hydroxydeoxyguanosine (8-OHdG), calcium and oxalate), inflammatory and oxdative stress biomarkers (transforming growth factor beta (TGF-β), osteopontin (OPN) and ratio of reduced glutathione to oxidized glutathione (GSH/GSSG)) in renal tissue.

RESULTS

Serum (creatinine and urea), urinary (8-OHdG and oxalate) and renal (OPN and TGF-β) were significantly reduced in CAND and STS groups compared to EG group. Furthermore, renal GSH/GSSG and urinary calcium were significantly increased in CAND and STS groups compared to EG group. Histopathological results support the biochemical findings; CAND and STS groups showed less retention of crystals and necrotic damage in kidney. Also, microscopic examination of urine revealed less crystal for CAND and STS groups.

CONCLUSION

Candesartan and sodium thiosulfate exhibited protective effect against nephrolithiasis.

Phenolic acids from vegetables: A review on processing stability and health benefits

Phenolic acids are the most prominent group of bioactive compounds present in various plant sources. Hydroxybenzoic acids and hydroxycinnamic acids, the aromatic secondary metabolites imparting typical organoleptic characteristics to food are the major phenolic acids, and they are linked to several health benefits. Fruit and beverage crops being the richer sources of phenolic acids have been studied in depth, but phenolic acids from vegetables are largely overlooked. Though lesser in quantity in many vegetables, there is a need to explore the health benefits of the phenolic acids present in them. In this review, the importance of vegetables as a significant source of phenolic acids is emphasized. Vegetables being easily accessible throughout the year and consumed in larger quantities compared to fruits in our daily diet will probably contribute to significant health benefits. Since vegetables are often processed before consumption, the changes in phenolic acids as influenced by processing methods are highlighted. Best processing methods, pre-treatments and storage conditions for higher retention of phenolic acids have been highlighted to minimize their losses. The phenolic acids in vegetables and their health benefits have been cluster mapped, which may facilitate further research for nutraceutical development for specific health concerns. The processing stability of phenolic acids coupled with higher consumption indicates that they may be a potential source of phenolic acids in the diet. It is expected that the popularization of vegetables as a source of phenolic acids in daily diet will help in ameliorating the adverse effect of some of the lifestyle diseases.

Hydroxycinnamic acids and human health: recent advances

There is an urgent need to improve human diet globally. Compelling evidence gathered over the past several decades suggests that a suboptimal diet is associated with many chronic diseases and may be responsible for more deaths than any other risks worldwide. The main components in our diet that need higher intake are whole grains, fruit and vegetables, and nuts and seeds; all of these are important sources of dietary fiber and polyphenols. The health benefits of dietary fiber and polyphenols are also supported by several decades of valuable research. However, the conclusions drawn from interventional human trials are not straightforward and the action mechanisms in improving human health are not fully understood. Moreover, there is a great inter-individual variation caused by different individual capabilities of processing, absorbing and using these compounds effectively. Data on the bioavailability and bioefficacy of hydroxycinnamic acids (HCAs) are limited when compared to other classes of polyphenols (e.g. anthocyanins). This review aims to summarize the latest research advances related to HCA bioavailability and their biological effects revealed by epidemiological data, pre-clinical and clinical studies. Moreover, we aim to review the effects of HCAs on gut microbiota diversity and function and its respective influence on host health. © 2019 Society of Chemical Industry.

Metabolomic analysis reveals a protective effect of Fu-Fang-Jin-Qian-Chao herbal granules on oxalate-induced kidney injury

Nephrolithiasis is one of the world’s major public health burdens with a high incidence and a risk of persistent renal dysfunction. Fu-Fang-Jin-Qian-Chao granules (FFJQC), a traditional Chinese herb formula, is commonly used in treatment of nephrolithiasis. However, the therapeutic mechanism of FFJQC on kidney stone has still been a mystery. The objective of the present study is to explore the therapeutic mechanism of FFJQC on kidney injury and identify unique metabolomics patterns using a mouse model of kidney stone induced by a calcium oxalate (CaOx) deposition. Von Kossa staining and immuno-histopathological staining of osteopontin (OPN), cluster of differentiation 44 (CD44) and calbindin-D28k were conducted on renal sections. Biochemical analysis was performed on serum, urine, and kidney tissues. A metabolomics approach based on ultra-HPLC coupled with quadrupole-TOF-MS (UHPLC-Q-TOF/MS) was used for serum metabolic profiling. The immunohistopathological and biochemical analysis showed the therapeutic benefits of FFJQC. The expression levels of OPN and CD44 were decreased while calbindin-D28k increased after the CaOx injured mice were treated with FFJQC. In addition, total of 81 serum metabolites were identified to be associated with protective effects of FFJQC on CaOx crystal injured mice. Most of these metabolites were involved in purine, amino acid, membrane lipid and energy metabolism. Potential metabolite biomarkers were found for CaOx crystal-induced renal damage. Potential metabolite biomarkers of CaOx crystal-induced renal damage were found. FFJQC shows therapeutic benefits on CaOx crystal injured mice via regulation of multiple metabolic pathways including amino acids, purine, pyrimidine, glycerolipid, arachidonic acid (AA), sphingolipid, glycerophospholipid, and fatty acid.

Genomic sequencing, genome-scale metabolic network reconstruction, and in silico flux analysis of the grape endophytic fungus Alternaria sp. MG1

BACKGROUND

Alternaria sp. MG1, an endophytic fungus isolated from grape, is a native producer of resveratrol, which has important application potential. However, the metabolic characteristics and physiological behavior of MG1 still remains mostly unraveled. In addition, the resveratrol production of the strain is low. Thus, the whole-genome sequencing is highly required for elucidating the resveratrol biosynthesis pathway. Furthermore, the metabolic network model of MG1 was constructed to provide a computational guided approach for improving the yield of resveratrol.

RESULTS

Firstly, a draft genomic sequence of MG1 was generated with a size of 34.7 Mbp and a GC content of 50.96%. Genome annotation indicated that MG1 possessed complete biosynthesis pathways for stilbenoids, flavonoids, and lignins. Eight secondary metabolites involved in these pathways were detected by GC-MS analysis, confirming the metabolic diversity of MG1. Furthermore, the first genome-scale metabolic network of Alternaria sp. MG1 (named iYL1539) was reconstructed, accounting for 1539 genes, 2231 metabolites, and 2255 reactions. The model was validated qualitatively and quantitatively by comparing the in silico simulation with experimental data, and the results showed a high consistency. In iYL1539, 56 genes were identified as growth essential in rich medium. According to constraint-based analysis, the importance of cofactors for the resveratrol biosynthesis was successfully demonstrated. Ethanol addition was predicted in silico to be an effective method to improve resveratrol production by strengthening acetyl-CoA synthesis and pentose phosphate pathway, and was verified experimentally with a 26.31% increase of resveratrol. Finally, 6 genes were identified as potential targets for resveratrol over-production by the recently developed methodology. The target-genes were validated using salicylic acid as elicitor, leading to an increase of resveratrol yield by 33.32% and the expression of gene 4CL and CHS by 1.8- and 1.6-fold, respectively.

CONCLUSIONS

This study details the diverse capability and key genes of Alternaria sp. MG1 to produce multiple secondary metabolites. The first model of the species Alternaria was constructed, providing an overall understanding of the physiological behavior and metabolic characteristics of MG1. The model is a highly useful tool for enhancing productivity by rational design of the metabolic pathway for resveratrol and other secondary metabolites.

In Vitro Antilithiatic Potential of Kalanchoe pinnata, Emblica officinalis, Bambusa nutans, and Cynodon dactylon

OBJECTIVE

The study aims at the exploration of calcium oxalate (CaOx) crystal growth inhibition potential of Cynodon dactylon, Emblica officinalis, Kalanchoe pinnata, and Bambusa nutans ethyl acetate fraction rich in polyphenol and flavonoid.

MATERIALS AND METHODS

Ethyl acetate fraction was separated from the hydromethanolic extract of C. dactylon, E. officinalis, K. pinnata, and B. nutans followed by quantitative analysis for total polyphenol and flavonoid content. Ethyl acetate fraction of all the plants were subjected to in vitro screening for the inhibition of CaO x crystals growth induced by sodium oxalate.

RESULTS

The results signify rich presence of polyphenols and flavonoids in K. pinnata and E. officinalis ethyl acetate fractions followed by C. dactylon and B. nutans. Ethyl acetate fractions of B. nutans shoot, E. officinalis fruit, and K. pinnata leaf have excellent in vitro CaO x crystal growth inhibition potential based on both the comparative concentration and the time level to achieve IC50.

CONCLUSION

The study outcome substantiates potential in vitro CaO x crystal dissolution and crystal growth inhibition properties of E. officinalis, B. nutans, C. dactylon, and K. pinnata. Rich presence of caffeic acid, ferulic acid, and luteolin in ethyl acetate fraction of B. nutans leaf, and chebulinic acid, chebulagic acid, gallic acid, ellagic acid, and quercetin of E. officinalis may have produced prominent crystal aggregation inhibition response.