The Inhibitory Effect of Non-Steroidal Anti-Inflammatory Drugs (NSAIDs) on the Monophenolase and Diphenolase Activities of Mushroom Tyrosinase

In the present work, we investigated the effect of non-steroidal anti-inflammatory drugs (NSAIDs) on the monophenolase and diphenolase activity of mushroom tyrosinase. The results showed that diflunisal and indomethacin inhibited both monophenolase and diphenolase activity. For monophenolase activity, the lag time was extended in the presence of diflunisal. In the presence of indomethacin, the lag time did not change. IC50 values of monophenolase activity were estimated to be 0.112 mM (diflunisal) and 1.78 mM (indomethacin). Kinetic studies of monophenolase activity revealed that both diflunisal and indomethacin were non-competitive inhibitors. For diphenolase activity, IC50 values were estimated to be 0.197 mM (diflunisal) and 0.509 mM (indomethacin). Diflunisal and indomethacin were also found to be non-competitive diphenolase inhibitors

Rationale and design of a multicenter randomized controlled study to evaluate the preventive effect of ipragliflozin on carotid atherosclerosis : the PROTECT study

Background: Type 2 diabetes mellitus is associated strongly with an increased risk of micro- and macro-vascular complications, leading to impaired quality of life and shortened life expectancy. In addition to appropriate glycemic control, multi-factorial intervention for a wide range of risk factors, such as hypertension and dyslipidemia, is crucial for management of diabetes. A recent cardiovascular outcome trial in diabetes patients with higher cardiovascular risk demonstrated that a SGLT2 inhibitor markedly reduced mortality, but not macro-vascular events. However, to date there is no clinical evidence regarding the therapeutic effects of SGLT2 inhibitors on arteriosclerosis. The ongoing PROTECT trial was designed to assess whether the SGLT2 inhibitors, ipragliflozin, prevented progression of carotid intima-media thickness in Japanese patients with type 2 diabetes mellitus. Methods: A total of 480 participants with type 2 diabetes mellitus with a HbA1c between 6 and 10 % despite receiving diet/exercise therapy and/or standard anti-diabetic agents for at least 3 months, will be randomized systematically (1:1) into either ipragliflozin or control (continuation of conventional therapy) groups. After randomization, ipragliflozin (50–100 mg once daily) will be added on to the background therapy in participants assigned to the ipragliflozin group. The primary endpoint of the study is the change in mean intima-media thickness of the common carotid artery from baseline to 24 months. Images of carotid intima-media thickness will be analyzed at a central core laboratory in a blinded manner. The key secondary endpoints include the change from baseline in other parameters of carotid intima-media thickness, various metabolic parameters, and renal function. Other cardiovascular functional tests are also planned for several sub-studies. Discussion: The PROTECT study is the first to assess the preventive effect of ipragliflozin on progression of carotid atherosclerosis using carotid intima-media thickness as a surrogate marker. The study has potential to clarify the protective effects of ipragliflozin on atherosclerosis

The Inhibitory Effect of Non-Steroidal Anti-Inflammatory Drugs (NSAIDs) on the Monophenolase and Diphenolase Activities of Mushroom Tyrosinase

In the present work, we investigated the effect of non-steroidal anti-inflammatory drugs (NSAIDs) on the monophenolase and diphenolase activity of mushroom tyrosinase. The results showed that diflunisal and indomethacin inhibited both monophenolase and diphenolase activity. For monophenolase activity, the lag time was extended in the presence of diflunisal. In the presence of indomethacin, the lag time did not change. IC50 values of monophenolase activity were estimated to be 0.112 mM (diflunisal) and 1.78 mM (indomethacin). Kinetic studies of monophenolase activity revealed that both diflunisal and indomethacin were non-competitive inhibitors. For diphenolase activity, IC50 values were estimated to be 0.197 mM (diflunisal) and 0.509 mM (indomethacin). Diflunisal and indomethacin were also found to be non-competitive diphenolase inhibitors

Depigmenting effect of catechins

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Depigmenting mechanism of NSAIDs on B16F1 melanoma cells

The aim of the present work was to clarify the anti-melanogenic mechanism of non-steroidal anti-inflammatory drugs (NSAIDs). Mefenamic acid, diclofenac, and nimesulide were used in this study, and these drugs inhibit melanin synthesis in B16F1 melanoma cells. To elucidate the anti-melanogenic mechanism of NSAIDs, we performed western blotting analysis for melanogenic proteins, such as tyrosinase, TRP-1, and TRP-2. All NSAIDs used in this study inhibited tyrosinase protein level. Semi-quantitative RT-PCR analysis showed that the depigmentation effect of mefenamic acid and nimesulide might be due to the inhibition of tyrosinase gene transcription. These results indicate that NSAIDs inhibit α-MSH-enhanced melanin synthesis, and are candidate anti-melanogenic agents since they might be effective in hyperpigmentation disorders.autho

Critical angioedema induced by a renin angiotensin system blocker in the contemporary era of increasing heart failure: A case report and commentary

Abstract Bradykinin‐mediated angioedema, a nonallergic reaction most commonly caused by renin angiotensin system (RAS) blockers, has the potential to lead to a critical condition. RAS blockers are important for treating heart failure and are widely used in clinical settings. We present the case of an 85‐year‐old man who was administered enalapril after percutaneous coronary intervention for an acute myocardial infarction and developed severe angioedema requiring a tracheostomy. He had multiple risks for angioedema including advanced age, smoking history, renal dysfunction, and longstanding use of an angiotensin receptor blocker. The prompt diagnosis of drug‐induced angioedema is critical and depends on physicians' recognition of risk factors and knowledge of pathophysiology. In the present era of increasingly prevalent heart failure, it is imperative that the possibility of angioedema receives attention, especially given the continuing reliance on RAS blockers and the advent of angiotensin receptor neprilysin inhibitors, a new type of heart failure drug