Osteoporosis and sarcopenia are two aspects of the geriatric syndrome that frequently occur together and affect one another in a condition referred to as osteosarcopenia. Preventive and treatment options for osteosarcopenia exist but are mainly focused on the treatment of osteoporosis, as there is still no FDA-approved treatment for sarcopenia. Drugs for osteoporosis include antiresorptive and anabolic drugs and hormonal replacement therapies and are prescribed based on age, BMD and other patient characteristics, which, however, do not include the possible co-existence of sarcopenia. As several studies and clinical trials have shown that the pharmacological treatment of osteoporosis can also affect muscle tissue, in either a positive or negative manner, sarcopenia should be another factor affecting the choice of treatment, especially when facing equal treatment options for osteoporosis. The aim of this review was to summarize our current knowledge on the effects of FDA-approved drugs for the treatment of osteoporosis on muscle quality, mass and function. A better understanding of the effects that certain drugs have on muscle tissue might in the future help us to simultaneously at least partially also address the wasting of muscle tissue and avoid further pharmacologically induced decline.

Many patients suffering from inherited diseases do not receive a genetic diagnosis and are therefore excluded as candidates for treatments, such as gene therapies. Analyzing disease gene transcripts from patient cells holds potential for detection and interpretation of causative variants, but may be complicated by unavailability of affected tissue and/or lack of expression of the respective genes in blood or other easily accessible tissues. Using CRISPR/Cas-mediated transcriptional activation (CRISPRa), we developed a robust and efficient approach to activate genes in skin-derived fibroblasts and in freshly isolated peripheral blood mononuclear cells (PBMCs) from healthy individuals. This approach was successfully applied to blood samples from patients with inherited retinal dystrophies (IRDs). We were able to efficiently activate several IRD genes and detect their transcript isoforms using different diagnostically relevant methods such as RT-(q)PCR and long- and short-read RNA sequencing. CRISPRa-mediated transcriptional activation in PBMCs and fibroblasts will contribute to closing the critical gap in the genetic diagnosis of patients with IRD or other inherited diseases.