Blueberry, cranberry, raspberry, and strawberry as modulators of the gut microbiota: target for treatment of gut dysbiosis in chronic kidney disease? From current evidence to future possibilities

Raspberry ameliorates renal fibrosis in rats with chronic kidney disease via the PI3K/Akt pathway

BACKGROUND

Renal fibrosis is a hallmark of chronic kidney disease (CKD). In traditional Chinese medicine, Rubus chingii Hu (raspberry) is believed to have kidney-tonifying properties. However, whether raspberry can effectively treat CKD, along with the specific active compounds and underlying mechanisms, remains unclear.

PURPOSE

This study aims to investigate the potential of raspberries in treating CKD and elucidate the mechanisms involved.

METHODS

CKD model was established in rats using adenine. The effects of raspberry treatment on CKD were assessed through macroscopic observations and pathological changes in the kidney. The expression of fibrotic proteins in renal tissues was analyzed to evaluate the impact of raspberry on renal fibrosis. Data mining combined with compositional analysis were employed to identify the active ingredients, targets, and pathways of raspberry that may improve CKD. Subsequently, Western blotting and immunofluorescence analysis were conducted to confirm the involvement of the PI3K/AKT signaling pathway in the renoprotective mechanism of raspberry.

RESULTS

Raspberry treatment significantly alleviated renal pathological damage, fibrosis and inflammation in model rats, showing effects comparable to irbesartan (Avapro). Chemical composition analysis and network pharmacology predicted AKT1 as the core target, and the PI3K/AKT pathway plays a pivotal role in mediating the therapeutic effects of raspberry extract in CKD. Molecular docking studies further confirmed that active compounds in raspberry have a strong binding affinity with AKT1. Western blotting and immunofluorescence results demonstrated that raspberry inhibited phosphorylation, thereby suppressing the PI3K/AKT pathway, leading to its antifibrotic effect on the kidney.

CONCLUSION

Raspberry was firstly discovered to potentially treat CKD by alleviating renal fibrosis through inhibition of the PI3K/AKT pathway. Raspberry, as a medicinal and edible traditional herb, could serve as a promising therapeutic agent or health supplement for improving renal fibrosis and slowing CKD progression.

Nutritional Intervention and Musculoskeletal Health in Chronic Kidney Disease

Chronic kidney disease (CKD) is a leading condition in terms of prevalence and overall health impact. With the increased life expectancy of the CKD population and the improvement in medical care, controlling musculoskeletal complications remains a tough challenge. Patients with CKD are prone to falls, fractures and sarcopenia, enhancing the risk of death. A multitude of mechanisms contribute to fractures, and treatment is suboptimal; therefore, prevention must stand out as a key step. This review aims to provide an overview of the most relevant data regarding the impact of nutrition on bone disorders and sarcopenia in CKD. The newest relevant studies emphasize that plant protein intake is associated with a lower production of uremic toxins, lower serum phosphorus levels, and stronger bones. We conclude that patients with CKD should adopt specific diets tailored to the presence of osteoporosis, renal osteodystrophy, and muscle wasting. Low-protein diets or plant-dominant diets containing an adequate amount of protein could be better choices for predialysis patients with CKD in order to protect their bones and muscles, whereas in the dialysis population, a higher protein intake could be essential to prevent osteoporosis and sarcopenia. In all patients with CKD, focusing on antioxidant food intake could provide a strong antiaging benefit through ensuring good musculoskeletal health.

Cranberry: A Promising Natural Product for Animal Health and Performance

Cranberries are a distinctive source of bioactive compounds, containing polyphenols such as flavonoids, anthocyanins, phenolic acids, and triterpenoids. Cranberries are often associated with potential health benefits for the urinary tract and digestive system due to their high antioxidant, anti-inflammatory, antimicrobial, and immunomodulatory properties. Cranberry induces the production of antioxidant enzymes, suppresses lipid peroxidation, reduces inflammatory cytokines, modulates immune cells, maintains gut microbiota, and inhibits bacterial adhesion and growth. Cranberry polyphenols also have metal-binding motifs that bind with metals, particularly zinc and iron. The combination of cranberry polyphenols and metals displays increased biological activity. In this review, an attempt is made to describe the physiological properties and health benefits of cranberries for livestock, including poultry, swine, canine, feline, and ruminant animals, as either feed/food or as supplements. Cranberry, and/or its components, has the capability to potentially control infectious diseases like diarrhea, urinary tract infection, gut integrity, and intestinal probiotic health. Moreover, cranberries show efficacy in suppressing the growth of pathogenic microorganisms such as Salmonella species, Campylobacter species, Streptococcus species, and Enterococcus species bacteria. Thus, cranberry could be considered as a potential natural feed additive or food supplement for animal health improvement.

Exploring Therapeutic Potential of Phytoconstituents as a Gut Microbiota Modulator in the Management of Neurological and Psychological Disorders

The functioning of the brain and its impact on behavior, emotions, and cognition can be affected by both neurological and psychiatric disorders that impose a significant burden on global health. Phytochemicals are helpful in the treatment of several neurological and psychological disorders, including anxiety, depression, Huntington's disease (HD), Parkinson's disease (PD), Alzheimer's disease (AD), and autism spectrum disorder (ASD), because they have symptomatic benefits with few adverse reactions. Changes in gut microbiota have been associated with many neurological and psychiatric conditions. This review focuses on the potential efficacy of phytochemicals such as flavonoids, terpenoids, and polyphenols in regulating gut flora and providing symptomatic relief for a range of neurological and psychological conditions. Evidence-based research has shown the medicinal potentials of these phytochemicals, but additional study is required to determine whether altering gut microbiota might slow the advancement of neurological and psychological problems.

Association of NAFLD/NASH, and MAFLD/MASLD with chronic kidney disease: an updated narrative review

Chronic kidney disease (CKD) and nonalcoholic fatty liver disease (NAFLD), metabolic dysfunction-associated fatty liver disease (MAFLD) and metabolic dysfunction-associated steatotic liver disease (MASLD) account for substantial financial burden worldwide. These alarming features call for enhanced efforts to prevent and manage the development and progression of CKD. Accumulating evidence supporting a causal role of NAFLD/MAFLD/MASLD-in CKD opens new horizons to achieve this aim. Recent epidemiological studies and meta-analyses exploring the association of NAFLD/MAFLD/MASLD with CKD and the characteristics of NAFLD/MAFLD/MASLD associated with the odds of incident CKD are discussed. The involved pathomechanisms, including the common soil hypothesis, genetics, gut dysbiosis, and portal hypertension, are examined in detail. Finally, lifestyle changes (diet and physical exercise), direct manipulation of gut microbiota, and drug approaches involving statins, renin-angiotensin-aldosterone system inhibitors, GLP-1 Receptor Agonists, Sodium-glucose cotransporter-2, pemafibrate, and vonafexor are examined within the context of prevention and management of CKD among those with NAFLD/MAFLD/MASLD. The evolving NAFLD/MAFLD/MASLD nomenclature may generate confusion among practicing clinicians and investigators. However, comparative studies investigating the pros and contra of different nomenclatures may identify the most useful definitions among NAFLD/MAFLD/MASLD and strategies to identify, prevent, and halt the onset and progression of CKD.

Food to Prevent Vascular Calcification in Chronic Kidney Disease

Vascular calcification (VC) is a consequence of chronic kidney disease (CKD) which is of paramount importance regarding the survival of CKD patients. VC is far from being controlled with actual medication; as a result, in recent years, diet modulation has become more compelling. The concept of medical nutritional therapy points out the idea that food may prevent or treat diseases. The aim of this review was to evaluate the influence of food habits and nutritional intervention in the occurrence and progression of VC in CKD. Evidence reports the harmfulness of ultra-processed food, food additives, and animal-based proteins due to the increased intake of high absorbable phosphorus, the scarcity of fibers, and the increased production of uremic toxins. Available data are more supportive of a plant-dominant diet, especially for the impact on gut microbiota composition, which varies significantly depending on VC presence. Magnesium has been shown to prevent VC but only in experimental and small clinical studies. Vitamin K has drawn considerable attention due to its activation of VC inhibitors. There are positive studies; unfortunately, recent trials failed to prove its efficacy in preventing VC. Future research is needed and should aim to transform food into a medical intervention to eliminate VC danger in CKD.

Gut Microbiota Interventions to Retain Residual Kidney Function

Residual kidney function for patients with chronic kidney disease (CKD) is associated with better quality of life and outcome; thus, strategies should be implemented to preserve kidney function. Among the multiple causes that promote kidney damage, gut dysbiosis due to increased uremic toxin production and endotoxemia need attention. Several strategies have been proposed to modulate the gut microbiota in these patients, and diet has gained increasing attention in recent years since it is the primary driver of gut dysbiosis. In addition, medications and faecal transplantation may be valid strategies. Modifying gut microbiota composition may mitigate chronic kidney damage and preserve residual kidney function. Although various studies have shown the influential role of diet in modulating gut microbiota composition, the effects of this modulation on residual kidney function remain limited. This review discusses the role of gut microbiota metabolism on residual kidney function and vice versa and how we could preserve the residual kidney function by modulating the gut microbiota balance.