Protective effects of hydrogen sulfide pretreatment on cyclophosphamide-induced bladder dysfunction in rats via suppression of bladder afferent nerves

Activation of the adenosine A1 receptor in the lumbosacral spinal cord improves bladder overactivity in rats with cystitis induced by cyclophosphamide

PURPOSE

To investigate the effect of intrathecal administration of CCPA, an adenosine A1 receptor agonist, on voiding function in rats with cystitis induced by cyclophosphamide (CYP).

METHODS

Thirty 8-week-old Sprague Dawley rats were randomly divided into a control group (n = 15) and a cystitis group (n = 15). Cystitis was induced by a single intraperitoneal injection of CYP (200 mg/kg, dissolved in physiological saline) in rats. Control rats were injected intraperitoneally with physiological saline. The PE10 catheter reached the level of L6-S1 spinal cord through L3-4 intervertebral space for intrathecal injection. Forty-eight hours after intraperitoneal injection, urodynamic tests were conducted to observe the effect of intrathecal administration of 10% dimethylsulfoxide (vehicle) and 1 nmol CCPA on micturition parameters, including basal pressure (BP), threshold pressure (TP), maximal voiding pressure (MVP), intercontraction interval (ICI), voided volume (VV), residual volume (RV), bladder capacity (BC), and voiding efficiency (VE). Histological changes of the bladder of cystitis rats were studied through hematoxylin-eosin staining (HE staining). Moreover, Western blot and immunofluorescence were used to study the expression of adenosine A1 receptor in the L6-S1 dorsal spinal cord in both groups of rats.

RESULTS

HE staining revealed submucosal hemorrhage, edema, and inflammatory cell infiltration in the bladder wall of cystitis rats. The urodynamic test showed significant increase in BP, TP, MVP and RV in cystitis rats, while ICI, VV, BC and VE decreased significantly, indicating bladder overactivity. CCPA inhibited the micturition reflex in both control and cystitis rats, and significantly increased TP, ICI, VV, BC, and VE, but had no significant effect on BP, MVP and RV. Western blot and immunofluorescence showed that there was no significant difference in the expression of adenosine A1 receptor in the L6-S1 dorsal spinal cord between the control and cystitis rats.

CONCLUSION

The findings of this study suggest that intrathecal administration of the adenosine A1 receptor agonist CCPA alleviates CYP-induced bladder overactivity. Furthermore, our results indicate that the adenosine A1 receptor in the lumbosacral spinal cord may be a promising target for treatment of bladder overactivity.

The hepato-protective effect of H2S-modified and non-modified mesenchymal stem cell exosomes on liver ischemia-reperfusion injury in mice: The role of MALAT1

INTRODUCTION

Ischemia-reperfusion injury (IRI) by causing histopathological changes is considered one of the most important causes of liver failure and dysfunction after surgery which affect graft outcomes. Stem cells are new promising approaches to treating different diseases. One of the critical strategies to improve their function is the preconditioning of their culture medium. This study compared the effect of NaHS-modified and non-modified mesenchymal stem cell exosomes on liver ischemia-reperfusion injury in mice.

METHODS

Human umbilical cord-derived MSC (MSC) cultured in a 75 cm3 flask and when confluency reached about 80%, the culture medium replaced with a serum-free medium, and 48 h later supernatants collected, concentrated, and then MSC-Exo extracted. To obtain H2S-Exo, MSC was treated with NaHS (1 μmol),the supernatant collected after 48 h, concentrated and exosomes extracted. Twenty-four male mice were randomly divided into four groups (n = 6) including: 1-ischemia, 2-sham-operated, 3- MSC-Exo, and 4- H2S-Exo. To induce ischemia, the hepatic artery and portal vein clamped using an atraumatic clip for 60 min followed by 3 h of reperfusion. Just upon ending the time of ischemia (removal of clamp artery), animals in MSC-Exo, and H2S-Exo groups received 100 μg exosomes in 100 μl PBS via tail vein. At the end of reperfusion, blood, and liver samples were collected for further serological, molecular, and histological analyses.

RESULTS

Administration of both MSC-Exo and H2S-Exo improved liver function by reducing inflammatory cytokines, cellular apoptosis, liver levels of total oxidant status, and liver aminotransferases. The results showed that protecting effect of MSC exosomes enhanced following NaHS preconditioning of cell culture medium.

CONCLUSION

MSC-Exo and H2S-Exo had hepato-protective effects against injuries induced by ischemia-reperfusion in mice. NaHS preconditioning of mesenchymal stem cells could enhance the therapeutic effects of MSC-derived exosomes.