This study investigated the effect of Catha edulis (khat) on some important parameters of the metabolic syndrome in Wistar Ottawa Karlsburg W (WOKW) rat. The animals were fed with the standard chow containing 5% air dried pulverized khat leaves for 14 days; followed by the standard chow for 16 days. The khat leaves were sorted into green (khat light; KL) and crimson (khat dark; KD) leaves. The control rats were fed on standard chow. Blood glucose (G), serum insulin, serum leptin and serum lipids (triglycerides, total cholesterol, HDL-, LDL-, and VLDL cholesterol) were determined. Feeding with khat leaves reduced the body weight and the triglyceride level of the animals. The effect of KD on these parameters was stronger than that of KL. KD lowered the blood glucose concentration and the leptin content whereas KL was inactive. The khat intake had no significant influence on serum insulin, total serum cholesterol, HDL-, LDL- and VLDL-cholesterol.

The present study evaluates the anti-diabetics and glycemic control of type 2 diabetic patients attending the out-patients clinics Aden. It is a cross-sectional study carried out in Aden Diabetic Center at Al-Gamhouria General Modern Hospital, Aden. Thirty two type-2-patients attended the center during the period from 15 January to 15 February 2018, using anti-diabetic drugs for more than one year, were included. Data were collected through direct interviews using a structured questionnaire, including patients characteristics as well as medical and medications characteristics. Blood samples were drawn to measure glycated hemoglobin HbA1c. Data were analyzed by using SPSS. (Version 22). Thirty seven and a half percent were females and 62.5% males. The mean age of the participants was 55 ±8.23 years. 56.2% of the patients showed good adherence to the exercise with the preponderance to the males, p=0.043. The mean BMI of the participants was 26.62± 3.89 Kg/m2, with half of them considered overweight (25-29.9 Kg/m2), while almost one fifth of the samples were obese. Half of the patients had hypertension and high cholesterol as comorbid conditions. The most frequent antidiabetic classes utilized by the patients were sulfonylureas, 62.5% and biguanides 62.5%. There was a limited use of DPP-4 inhibitors, sitagliptin and alogliptin (6.2%). 53.1% of the studied patients utilized monotherapy, followed by a combination of oral antidiabetics 37.55%, and a combination of oral antidiabetics and insulin (9.3%). The mean value of HbA1c of the samples studied was 9.65 ±2.33%. Only 12.5% of the patients had good glycemic control and 87.5% of the participants had HbA1c of ≥ 7 %. Almost forty percent of the patients with HbA1c ≥7% had cardiovascular diseases such as hypertension and higher cholesterol (p=0.019). In conclusion, the most frequent antidiabetic classes utilized by type-2-patients who attended outpatients clinics were sulfonylureas and biguanides with a tendency to use combination regimens. The majority of patients had poor glycemic control associated with cardiovascular morbidity. Attention should be given on the treatment regimens and dosage.

Metformin is the first-choice drug for treatment of type 2 diabetes notably those associated with obesity. It does not only reduce hyperglycemia, but also possesses pleiotropic effects opening the pave for numerous potential clinical applications. In this chapter we illustrate the various mechanisms of metformin action in reduction of hepatic glucose output, improvement of insulin action, restoration of fat metabolism and gut microbiome, reduction of inflammation, upregulation of antioxidant enzymes, and attenuation of tumor growth. Understanding of such mechanisms might propose further clinical applications for metformin.

The study investigated the effect of methanol extract and its fractionations obtained from Yemeni khat on the smooth muscle isometric tension in Lewis rat aortal ring preparations and compared the effects of the crimson and green leaves. Khat leaves were sorted into green (khat Light; KL) and crimson (khat Dark; KD) leaves, extracted with methanol, followed with solvent-solvent extraction (benzene, chloroform and ethylacetate). The contractile activity of the fractions was tested using aortal ring preparations. The control (phenylepherine contraction) methanol extracts contracted aortas at concentrations 250, 125 and 67.5 µg /1 ml buffer by 80.2% , 57.3%, 26.4% and 81.5%, 65.6% , 24.6% for KL and KD, respectively. Fractions of benzene (BF) and ethylacetate (EaF) contracted the aorta with 2µgm, whereas, chloroform (ChF) with 1 µgm / 1 ml buffer was less potent. The shape of contraction curve produced by EaF differed from that of ChF and BF of both (KL and KD). The EaF induced-contraction peaked after 3.3 ± 0.94 mins, whereas those of BF and CHF peaked after 18.0 ± 2.2, 19.7 ± 0.94 mins, respectively. Pre-incubation with nifedipine (10-6 M) insignificantly reduced the contraction induced by all fractionations, but prazosin (10-6 M) reduced the contraction by 81.9%, 63.1%, 71.8% with p= 0.23, 0.09, 0.15 for BF, ChF and EaF of KL, respectively. It significantly reduced contraction of ChF, 64.1%; p= 0.02, and of EaF, 73.5%; p= 0.04 of KD, while the reduction in contraction of BF was 63.1%; p= 0.06. In conclusion, fractions of green and crimson Yemeni khat leaves contracted aortas of Lewis rats. Both leaves behave almost similarly. Contraction induced by chloroform fraction produced alphasympathetic activity.