12 research outputs found
Oocytes preserve the ability of mouse cumulus cells in culture to synthesize hyaluronic acid and dermatan sulfate
A soluble factor(s) produced by fully grown oocytes is essential, together with follicle stimulating hormone (FSH), to stimulate in vitro hyaluronic acid (HA) synthesis by mouse cumulus cells (CCs). The stability of the response to this stimulus by CCs in culture was investigated. The data showed that preculture for 8 hr in basal medium reduced to approximately 30% the ability of CCs to synthesize HA in response to FSH or dibutyryl cyclic AMP (Bt2cAMP) and soluble oocyte factor(s). However, if CCs were precultured for the same period of time as intact cumulus cell-oocyte complexes, or in the presence of fully grown oocytes, or in medium conditioned by fully grown oocytes, their ability to synthesize HA was 75-95% preserved. In vitro stimulation of dermatan sulfate (DS) synthesis by CCs does not require oocyte factors and is induced by FSH or Bt2cAMP treatment alone. However, the preservation of such activity, like that of HA synthesis, depended on the presence of a soluble oocyte factor(s) during preculture. The presence of isolated oocytes or of oocyte-conditioned medium also prevented the spreading of CCs in culture. However, inhibiting CC spreading by culture on agar-coated plates or in serum-free medium did not preserve their HA or DS synthetic activity, thus suggesting that the two oocyte actions on CCs are independent. Growing oocytes were unable both to induce HA synthesis in freshly isolated CCs stimulated with FSH and to preserve the ability to synthesize HA and DS in 8-hr precultured CCs. The results suggest that the stability of the differentiated state of mouse CCs in vitro depends upon continued exposure to a soluble factor(s) produced by fully grown oocytes
The epidemiology of partialandrogen deficiency in aging men (PADAM)
The quest for eternal youth has been prevalent in civilised societies in many cultures for many centuries. Preventing or deferring the disabilities and morbidities associated with aging through judicious pharmacotherapy has become a particularly relevant healthcare target with the rapid and relentless global demographic shift towards an increasingly elderly population in the 21th century. Aging men commonly loose muscle, become frail, have impaired sexual and cognitive functions, low mood, develop osteopenia and/or osteoporosis with increased risk for fractures and gain visceral fat which predisposes to diabetes, dyslipidaemia, and ischemic heart disease. These alterations in body function are reminiscent of states of androgen deficiency in younger patients. Indeed, aging is associated with a progressive age-related but variable decline in sex hormones. This condition has been named partial androgen deficiency in aging men (PADAM) and consists in a gradual decline in sex hormone levels over years resulting in physical and psychological changes as depression, impotence, decreased sex drive, loss of muscle tone or strength and lethargy. In this review we have tried to give a real identity to PADAM and quantify its entitiy, using the power of the epidemiology