Abstract
Erectile dysfunction (ED) affects a significant proportion of men aged 40–70 and is caused by cavernous tissue dysfunction. Presently, the most common treatment for ED is phosphodiesterase 5 inhibitors; however, this is less effective in patients with severe vascular disease such as diabetic ED. Therefore, there is a need for development of new treatment, which requires a better understanding of the cavernous microenvironment and cell-cell communications under diabetic condition. Pericytes are vital in penile erection; however, their dysfunction due to diabetes remains unclear. In this study, we performed single-cell RNA sequencing to understand the cellular landscape of cavernous tissues and cell type-specific transcriptional changes in diabetic ED. We found a decreased expression of genes associated with collagen or extracellular matrix organization and angiogenesis in diabetic fibroblasts, chondrocytes, myofibroblasts, valve-related lymphatic endothelial cells, and pericytes. Moreover, the newly identified pericyte-specific marker, Limb Bud-Heart (Lbh), in mouse and human cavernous tissues, clearly distinguishing pericytes from smooth muscle cells. Cell–cell interaction analysis revealed that pericytes are involved in angiogenesis, adhesion, and migration by communicating with other cell types in the corpus cavernosum; however, these interactions were highly reduced under diabetic conditions. Lbh expression is low in diabetic pericytes, and overexpression of LBH prevents erectile function by regulating neurovascular regeneration. Furthermore, the LBH-interacting proteins (Crystallin Alpha B and Vimentin) were identified in mouse cavernous pericytes through LC-MS/MS analysis, indicating that their interactions were critical for maintaining pericyte function. Thus, our study reveals novel targets and insights into the pathogenesis of ED in patients with diabetes.
Competing Interest Statement
The authors have declared no competing interest.
Footnotes
1. We have clarified the specificity of Lbh as a pericyte marker in our dataset. Lbh exhibits specific expression patterns in both mouse and human penile tissues, but not in all the tissues we analyzed using Mouse Single Cell Atlas. Therefore, in some tissues, particularly in mouse penile tissue, Lbh may be a valuable marker for differentiating pericytes along with other established pericyte marker genes. 2. We have performed statistical analyses and added experimental data to support cell-cell communication and TF regulon analysis results. 3. We have emphasized the importance of the observed results related to the rescue of ED by Lbh overexpression and clarified the need for further mechanistic investigations in the discussion section. 4. We have acknowledged the limitation that our data may not definitively identify the specific cell types responsible for ED rescue and emphasized the need for further mechanistic studies. 5. We have added controls and performed Co-IP experiments to support the interaction between LBH and CRYAB/VIM1. The results provide evidence for the specific interaction of these proteins.
