These mechanisms are characterized as having a rapid onset (less than 15 minutes), because they do not rely on time-consuming transcription or translation and are not modified by inhibitors of transcription.Methylprednisolone induced non-genomic signaling is classified by three mechanisms: (1) cytoplasmic glucocorticoid receptor (cGR)-mediated non-genomic effects, (2) membrane-bound glucocorticoid receptor (mGR) non-genomic effects, and (3) physiochemical interactions with cellular membranes (non-specific non-genomic effects).Proteins that dissociate from the activated GC-cGR complex, initiate intracellular transcription-independent mechanisms. It is evidence that dissociated SRC is responsible for inhibiting the release of arachidonic acid (AA) from cell membrane phospholipids. AA is required for the synthesis of inflammatory mediators (prostaglandins and leukotrienes) and thus AA inhibition mediates several important pathways such as cellular growth, metabolism and inflammation.Previous studies identified mGRs in lymphoma cells, but it wasnt until 2004 that mGRs were identified in human peripheral mononuclear cells. The prevalence of mGRs ranges per cell type, with the highest concentration in B lymphocytes at up to 12.3%, up to 9.2% in monocytes, and absent from T lymphocytes. Studies have shown a positive correlation between the mGR-positive cells and disease related activity. There are no proven signaling pathways associated with mGR at this time. Some researchers hypothesize that high disease activity activates mGR expression and upon administering methylprednisolone, creates a negative feedback loop by inducing apoptosis.High concentrations of methylprednisolone intercalate in plasma and mitochondrial cellular membranes.
Methylprednisolone (Depo-Medrol, Medrol, Solu-Medrol) is a synthetic glucocorticoid, primarily prescribed for its anti-inflammatory and immunosuppressive effects. It is either used at low doses for chronic illnesses or used concomitantly at high doses during acute flares. Methylprednisolone and its derivatives can be administered orally or parenterally.Regardless of route of administration, methylprednisolone integrates systemically as exhibited by its effectiveness to quickly reduce inflammation during acute flares. It is associated with many adverse reactions that require tapering off the drug as soon as the disease is under control. Serious side effects include iatrogenic Cushings Syndrome, hypertension, osteoporosis, diabetes, infection, and skin atrophy.Chemically, methylprednisolone is a synthetic pregnane steroid hormone derived from hydrocortisone and prednisolone. It belongs to a class of synthetic glucocorticoids and more generally, corticosteroids. It acts as a mineralocorticoid and glucocorticoid receptor agonist. In comparison to other exogenous glucocorticoids, methylprednisolone has a higher affinity to glucocorticoid receptors than to mineralocorticoid receptors. Glucocorticoids name was derived after the discovery of their involvement in regulating carbohydrate metabolism. The cellular functions of glucocorticoids, such as methylprednisolone, are now understood to regulate homeostasis, metabolism, development, cognition, and inflammation. They play a critical role in adapting and responding to environmental, physical and emotional stress.Methylprednisolone was first synthesized and manufactured by The Upjohn Company (now Pfizer) and FDA approved in the United States in October 1957. In 2019, it was the 161st most commonly prescribed medication in the United States, with more than 3 million prescriptions.