Early Supplementation of d-Cysteine or l-Cysteine Prevents Hypertension and Kidney Damage in Spontaneously Hypertensive Rats Exposed to High-Salt Intake

Scope: We investigate whether early supplementation of precursors of hydrogen sulfide (H₂S), d- or l-cysteine can prevent hypertension and kidney damage in spontaneously hypertensive rats (SHR) treated with high-salt. Methods and Results: We examine 12-week-old male SHRs from four groups: SHR, high salt SHR (SHRs received 1% NaCl in drinking water for 8 weeks), high salt SHR+d (SHRs received high salt and d-cysteine), and high salt SHR+l (SHRs received high salt and l-cysteine). d- or l-cysteine was supplemented at 8 mmol kg⁻¹ body weight/day between 4 and 6 weeks of ages. High salt intake exacerbate hypertension and kidney damage in SHRs, which is prevented by d- or l-cysteine supplementation. d- or l-Cysteine supplementation reduce the degree of high salt-induced oxidative stress damage. Renal 3-mercaptopyruvate sulphurtransferase (3MST) protein levels and activity are reduced by d- or l-cysteine supplementation. Additionally, d- or l-Cysteine supplementation reduce renal angiotensin I and angiotensin II concentrations, decrease mRNA expression of Ren, and increase protein levels of type 2 angiotensin II receptor. Conclusion: Early supplementation of d- or l-cysteine before hypertension becomes evident and may protect against hypertension and kidney damage in adult SHRs exposed to high salt consumption via regulation of oxidative stress, renin-angiotensin system, and H₂S-generating pathways.