# Combination therapy with bone marrow-derived mesenchymal stem cell transplantation and propolis improves streptozotocin-induced kidney injury in diabetic rats

## TL;DR

Combining propolis and bone marrow stem cells helps improve kidney damage in diabetic rats, with effects similar to metformin.

## Contribution

This study introduces a novel combination therapy using propolis and MSCs for treating diabetic kidney injury in rats.

## Key findings

- Combination therapy with propolis and MSCs significantly lowers serum glucose in diabetic rats.
- Treatment groups showed improved serum albumin and reduced creatinine and urea levels compared to untreated diabetic rats.
- Renal index and histopathology improved in all treatment groups, comparable to metformin effects.

## Abstract

The aim of the current study was to determine the therapeutic effects of combination therapy with propolis extract and rat bone marrow mesenchymal stem cells (MSCs) in streptozotocin (STZ)-induced diabetic rats.

Firstly, characterization of MSCs was performed and MTT assay was done to determine the optimum concentration of propolis for incubation with MSCs. Rats were divided into 8 groups: Control, diabetic , diabetic+propolis, diabetic+metformin, diabetic+MSCs, diabetic+MSCs+ propolis, diabetic+ MSCs pre-incubated with propolis. MSCs were transplanted via the tail vein on the 7th and 21st days of the study. Renal function tests and histopathologic examination were performed for all groups.

Serum glucose concentration in all propolis and MSCs treatment groups was significantly lower than that of the STZ group on the 21st and 42nd days of the study. On the 42nd day, the concentration of serum albumin in the STZ group was significantly lower than the control. Serum albumin concentration in all diabetic groups treated with propolis and MSCs was significantly higher than the diabetic animals. On the 42nd day, the concentrations of creatinine and urea in the STZ group were significantly higher than all the treatment and control groups. The renal index and histopathological parameters improved in all treatment groups compared with the STZ group.

Our findings demonstrated, MSCs, propolis, and their combination demonstrate positive effects on renal function, kidney index, and histopathology in all treated animals compared with the STZ diabetic rats. These beneficial effects are comparable to those of metformin.