Nutraceutical potential of almond fruits in managing diabetes-related erectile dysfunction: Effect on Nrf-2 level and smooth muscle/collagen ratio

Andrologia. 2022 Dec;54(11):e14636. doi: 10.1111/and.14636. Epub 2022 Nov 8.


Oxidative stress is one of the major crosstalk between diabetes and erectile dysfunction. Tropical almond is a natural antioxidant that works in a way to neutralize the effect of reactive oxygen species in disease management. This study therefore aimed to evaluate the effects of tropical almond on the nuclear factor erythroid-2-related factor-2 (nrf-2) level and smooth muscle/collagen ratio, as well as other biochemical indices in the penile tissue of diabetic rats. Six non-diabetic male rats (control) and 36 diabetic male rats were divided into six groups (n = 6). The diabetic male rats were placed on almond-supplemented diets except for the diabetic control group. Thereafter, the rats were sacrificed penile tissues were excised for nrf-2, smooth muscle/collagen ratio, and other biochemical analyses. The results revealed a significant (p < 0.05) decrease in nrf-2 level, smooth muscle/collagen ratio, and total thiol level, with a concomitant increase in acetylcholinesterase activity in comparison to the control group. Interestingly, therapy with diets high in almond fruits significantly enhances the nrf-2 level, smooth muscle/collagen ratio, and total thiol level in comparison with the untreated diabetic group. In addition, dietary inclusion of almond fruits significantly reduced acetylcholinesterase activity in diabetic male rats. Therefore, the preventive management with almond fruits could be beneficial in combating erectile dysfunction associated with diabetes. The activities of almond fruits reported in this study could be due to their antioxidant property and the inherent phytoconstituents (amino acids, phenolic compounds, and flavonoids).

Keywords: Nrf-2; antioxidant; smooth muscle/collagen ratio; tropical almond.

MeSH terms

  • Acetylcholinesterase
  • Animals
  • Antioxidants / pharmacology
  • Antioxidants / therapeutic use
  • Collagen
  • Diabetes Mellitus, Experimental* / complications
  • Dietary Supplements
  • Erectile Dysfunction* / complications
  • Erectile Dysfunction* / etiology
  • Fruit
  • Humans
  • Male
  • Muscle, Smooth
  • Penile Erection
  • Penis
  • Prunus dulcis*
  • Rats
  • Rats, Sprague-Dawley
  • Sulfhydryl Compounds


  • Acetylcholinesterase
  • Antioxidants
  • Collagen
  • Sulfhydryl Compounds