Background: Both c-peptide and nicotinamide are known to increase blood insulin in diabetes. In the present study, we examined the effect of c-peptide alone or in combination with nicotinamide on insulin levels in pancreatic islets in mice. Methods: This study was conducted with 60 adult male Naval Medical Research Institute (NMARI) mice weighing 25 to 30 g. Pancreatic islets from normal mice were isolated by the collagenase digestion method. Mice were divided into ten groups of six (n = 6): control, glyburide (1 and 10 μM), C-peptide (50 and 100 nM), nicotinamide (10, 25, and 100 mM), nicotinamide + C-peptide (100 mM and 100 nM), and buffer in different glucose concentrations (2.8, 5.6, and 16.7 mM). Insulin secretion was measured using insulin radioimmunoassay method. Results: Insulin secretion significantly increased at 16.7 mM glucose concentration compared with 2.8 and 5.6 mM glucose concentrations. Incubation of islets at 2.8 and 5.6 mM glucose concentrations and nicotinamide + C-peptide, nicotinamide 25 and 100 mM, and C-peptide 100 nM significantly increased insulin secretion compared with the control group. In addition, incubation of islets at 16.7 mM glucose with nicotinamide + C-peptide significantly increased insulin secretion. Glyburide at 10 μM concentration was more effective than nicotinamide at 10 and 100 mM, C-peptide 50 and 100 nM in the presence of 16.7 mM glucose concentration. However, the combination of nicotinamide + C-peptide was more effective than glyburide at a concentration of 10 μM in the presence of a 16.7 mM glucose concentration. Conclusions: This paper suggests that c-peptide, nicotinamide, and the combination of c-peptide and nicotinamide in-creases insulin secretion from pancreatic islets.
C-Peptide ; Niacinamide

Background: Niacinamide is known for its anti-inflammatory effect and skin penetration capability. Currently, limited studies are available on its efficacy on psoriasis. Objective: This study aimed to determine the efficacy and safety of 4% niacinamide cream on mild to moderate psoriasis. Methods: 40 patients were randomly allocated to 4% niacinamide cream (N), or 0.1% triamcinolone acetonide cream (TAC) or 4% niacinamide cream and 0.1% triamcinolone acetonide cream (N-TAC) for 10 weeks treatment. A 50% improvement in psoriasis area severity index (PASI50) was considered as the primary endpoint of the study. Secondary outcome measures were physician global assessment (PGA), dermatology life quality index (DLQI), and adverse events. PASI and PGA were assessed biweekly. DLQI was assessed at the start and at the end of the study period. Results: PASI50 was achieved in 85% of patients in N-TAC, 75% of patients in TAC and 15% of patients in N. There was no statistical significant difference between groups TAC and N-TAC (p=0.645, Fisher’s exact test). A higher number of patients in N-TAC (31%) achieved PGA1 score or “almost clear” and reached PASI50 earlier (60% at week 4). A higher improvement in DLQI score was seen in N-TAC; however, mean DLQI improvement did not vary by treatment group (p=0.0770). No adverse event was reported for groups TAC and N-TAC while pruritus and erythema were noted in N. Conclusion: Monotherapy of 4% niacinamide cream was not effective in the treatment of mild to moderate psoriasis. The combination N-TAC showed a continuous and sustained improvement of lesions compared to monotherapy TAC.
triamcinolone acetonide ; niacinamide ; psoriasis

Erythema elevatum diutinum (EED) is a rare condition believed to be a form of chronic recurrent leukocytoclastic vasculitis possibly secondary to vascular immune complex deposition. The disease is characterized by symmetrical, red, brownish-purple, and yellow papules, plaques, and nodules distributed mainly over the extensor surfaces of the extremities. We report a 61-year-old male with an atypical presentation of such disease as a giant warty lesion on the heels. Histologically, a spectrum from leukocytoclastic vasculitis to vessel occlusion and dermal fibrosis is seen in EED. These histological findings were present in the histopathological reading of the patient which established its diagnosis and further ruled out verruca vulgaris. The disease is associated with many disease entities, which include human immunodeficiency virus, malignant conditions, chronic infection, and autoimmune and connective tissue disorders. None of these conditions was present in the patient as manifested in the history, physical, and laboratory examinations. However, the patient has a low hemoglobin and a G6PD deficiency which makes him a bad candidate for dapsone therapy which is the main treatment for EED. Tetracycline, niacinamide and plain vaseline + salicylic acid were given initially for 4 weeks but no improvement was noticed. It was then shifted to 10mg intralesional corticosteroid and urea paste 40%. Niacinamide still was given. There was a marked thinning of the lesions. The medications were continued and were slowly tapered. More improvement of the lesions was observed.
Glucosephosphate Dehydrogenase Deficiency ; Niacinamide

BACKGROUND: To reduce or prevent myocardial injury during an ischemia-reperfusion episode, some pharmacological interventions, including administering nicorandil or verapamil, have becomepopular in clinical situations. Nicorandil is a N-(2-hydroxyethyl)- nicotinamide nitrate ester, and it's effective mainly by opening the K+ ATP channels in the mitochondrial membrane, and verapamil is useful for reducing the endothelial injury of coronary vessels during ischemia. In this study, we aimed to determine the cardioprotective effect when both drugs are used simultaneously. METHODS: Isolated rat hearts (the Langendorff perfusion model) were perfused with Krebs-Henseleit bicarbonate buffer. After 30 minutes of controlled perfusion, we added nicorandil or verapamil separately and both drugs were administered together in another group (the mixed group) and we then induced ischemia for 30 minutes. We measured the heart rate, the developed ventricularpressure and the dP/dT during the control period during drug infusion and during reperfusion at 15, 30, 45 and 60 minutes. RESULTS: During reperfusion, the mixed group showed more favorable results for the developed left ventricular pressure (LVP), the dP/dT and the rate pressure product (RPP). The heart rate was significantly decreased as reperfusion processed in all the groups. CONCLUSIONS: For myocardial protection during ischemia-reperfusion, a mixed drug regimen is more beneficial than a single drug regimen, and this occurs without inducing a significant decrease of the heart rate.
Adenosine Triphosphate ; Animals ; Coronary Vessels ; Heart ; Heart Rate ; Ischemia ; Mitochondrial Membranes ; Niacinamide ; Nicorandil ; Perfusion ; Rats ; Reperfusion ; Ventricular Pressure ; Verapamil

The ability of nicotinic acid and its substitutes to increase cutaneous blood flow has been measured by laser Doppler flowmeter in 30 healthy human volunteers. We applied nicotinarnide, nicotinic acid ethyl ester, nicotinic acid methyl ester, hexyl nicozinate each in an acqeous solution at a concentration of 10 mM/liter for 10 minutes occlusion on the forearm. The change of blood flow was serially checked at 5 to 10 minutes intervals for one hour. The study results were as follows : l. The relative maximum cutaneous blood flow response was in following order nicotinic acid methyl ester(100%), nicotinic acid ethyl ester(98%), hexyl nicotinate (84%) and nicotinic acid(63%). However, there was no statistically significant difference(p>0.05) between each drug. There was statististically significant difference between nicotinamide and all other nicotinic acid substitutes(p<0.05). 2. The time required to reach maximum blood flow response was 6.7 minutes for hexyl nicotinste, 10 minutes for nicotinic acid ethyl ester, 12.5 minutes for nicotinic acid methyl ester and 20 minutes for nicotinic acid. However, there was statistically significant difference between hexyl nicotinate and nicotinic acid only(p<0.05). 3. Significant decrease of cutaneous blood flow was observed one hour after the removal of the patches in all drugs.
Flowmeters ; Forearm ; Healthy Volunteers ; Niacin* ; Niacinamide

There have been recent advances in the treatment of hepatocellular carcinoma (HCC). There has been a clear change in the presentation of HCC, with an increased detection of tumors <2 cm in diameter as result of surveillance programs. In addition, the development of effective local treatment methods has led to the necessity for the selection of base therapeutic modalities on each patient's characteristics. New promising image-guided therapies and new drugs, such as sorafenib, may address the enormous need for expanded treatment options for patients with HCC. Tailored therapies are needed to improve the treatment response and, ultimately, patient survival. Here, we review these advances in the management of HCC.
Carcinoma, Hepatocellular ; Humans ; Niacinamide ; Phenylurea Compounds

We evaluated the effect of nicotinamide on cellular O2 consumption and metabolic status i.e., adenylate phosphates and NAD+ in-vitro, and changes in blood flow in-vivo, to determine whether changes in cellular metabolism or increased oxygen availability, was responsible for increased tumor oxygenation. Thirty min. Pre-incubation of cells with~4mM (=500mg/kg) nicotinamide resulted in no change in cellular O2 consumption. Similarly, neither the adenylate phosphates nor the cellular NAD+ levels were altered in the presence of~4mM nicotinamide. In-vivo, nicotinamide (500mg/kg) increased O2availability as estimated by changes in relative tumor blood flow (RBC flux). The changes in RBC flux measured by the laser Doppler method, were tumor volume dependent and increased from~35% in~150mmdegree tumors to~75% in~500mmdegree tumors. In conclusion, these observations indicate a reduction in local tissue O2 consumption is not a mechanism of improved tumor oxygenation by nicotinamide in FsaII murine tumor model. The primary mechanism of increased pO2 appears to be an increased local tumor blood flow.
Laser-Doppler Flowmetry ; Metabolism ; Niacinamide ; Oxygen ; Phosphates ; Tumor Burden

Pellagra is a chronic wasting disorder characterized by 3 clinical distinct symptoms; dermatitis; dementia; and diarrhea. It results from a marked cellular deficiency of water-soluble vitamin B3, also called niacin. Dermatitis begins as an erythema and shows bilateral symmetrical eruption at cutaneous sites of solar exposure. Herein we report 2 cases of pellagra in chronic alcoholics.
Alcoholics* ; Dementia ; Dermatitis ; Diarrhea ; Erythema ; Humans ; Niacin ; Niacinamide ; Pellagra*

Pentoxifylline (PENTO) has been known to improve RBC fluidity, and thus improve the flux of RBC through narrow capillaries. Additionally, PENTO also decreases the O2 release from RBC. Nicotinamide (N4) has been reported to decrease the number of acutely hypoxic cells in tumors by temporarily increasing tumor blood flow. Therefore, the purpose of this study was to examine whether the combination of PENTO and NA (PENTO+NA) would reduce the radioresistance of the the FSaII murine fibrosarcoma by oxygenation the hypoxic cells. We observed a significantly enhanced radiation-induced growth delay of the FSaII tumors by PENTO-NA. Thus the enhancement ration was between 2.5 and 2.8 in growth delay assay. The TCD50 of control tumors was about 57 Gy, but that of PENTO-NA treated tumors was about 32 Gy. The TCD50 was modified by a factor of 1.8. We also observed that PENTO+NA, changes in tumor blood flow and intratumor pO2 were measured using laser Doppler flowmetry and O2 microelectrode methods. The tumor blood flow significantly increased at 10 min. after injection of PENTO+NA. Furthermore, we also found that PENTO+NA significantly increased intratumor pO2 from 8 to 19 mmHg. We concluded that PENTO+NA was far more effective than NA alone or PENTO alone. The increase in the response of tumor in vivo to X-irradiation appeared to be due mainly to an increase in the tumor oxygenation. Further studies using various concentrations of PENTO alone and in combination with NA to obtain better sequencing and maximal radiosensitization are warranted.
Capillaries ; Fibrosarcoma ; Laser-Doppler Flowmetry ; Microelectrodes ; Niacinamide* ; Oxygen ; Pentoxifylline*

Humans ; Leukemia, Myeloid, Acute ; Niacinamide ; analogs & derivatives ; Phenylurea Compounds