Effect of in vitro Digestion on the Bioaccessibility of Polyphenols and Potential Prebiotic Properties of Potato Peel

BACKGROUND

Potato peel is a byproduct of the potato processing industry and a potential source of functional ingredients such as dietary fiber, polyphenols, and prebiotics. However, the bioaccessibility of polyphenols and antioxidants during in vitro digestion and prebiotic potential after in vitro digestion of potato peel flour has not been reported.

OBJECTIVE

The study was designed to assess the bioaccessibility of polyphenols and the prebiotic potential of potato peel flour.

METHODS

In this study, the changes in polyphenol content and antioxidant capacity during different phases of in vitro digestion, including salivary, gastric and intestinal phases were studied. Additionally, an investigation was conducted to evaluate the prebiotic properties of potato peel flour by in vitro fermentation with Lactobacillus acidophilus.

RESULTS

The findings revealed a significant increase in the recovery index for total phenolic content during both gastric (106.90%) and intestinal (102.71%) digestive phases. Furthermore, polyphenols in potato peel flour exhibited high residual intestinal digestibility index values (>90%). The antioxidant capacity increased by >50% during various phases of in vitro digestion. Regarding prebiotic properties, potato peel flour significantly increased L. acidophilus counts and promoted the production of short-chain fatty acids, specifically propionate and butyrate.

CONCLUSION

This study suggests that potato peel flour has the potential to serve as a functional ingredient or nutraceutical that can enhance health and may help in reducing environmental problems.

Empagliflozin improves primary haemodynamic parameters and attenuates the development of atherosclerosis in high fat diet fed APOE knockout mice

The effects of long-term treatment with empagliflozin on biochemical and immunohistochemical markers related to atherosclerosis and atherosclerosis development in the aorta of apolipoprotein E knockout [Apo-E ^(-/-)] mice were evaluated in this study. Empagliflozin-treated mice had lower total cholesterol (P < 0.05), fasting glucose (P < 0.01), heart rate (P < 0.01) and diastolic blood pressure (DBP) (P < 0.05) compared to controls. Histomorphometry revealed reduced atherosclerotic lesion progress approaching statistical significance (P = 0.06) and approximately 50% wider lumen area for the Empagliflozin treated mice group. Although empagliflozin significantly reduced Vcam-1 and Mcp-1 (P < 0.05, P < 0.01, respectively) and marginally induced Timp-1 and Timp-2 mRNA expression (P < 0.08, P = 0.1 respectively), immunohistochemistry revealed a marginal reduction in VCAM-1 and MMP-9 (P = 0.1) without affecting the expression of TIMP-2 and MCP-1 in atherosclerotic lesions. Empagliflozin improves primary haemodynamic parameters and attenuates the progression of atherosclerosis by reducing hyperlipidemia and hyperglycemia, while direct actions in aorta vessel mediated via SGLT-1 are strongly hypothesized.

Total phenolic content and total antioxidant capacity of common Indian pulses and split pulses

Pulses are valued for their protein content and are good source of bioactive phytochemicals. The objectives of this study were to estimate total phenolic content (TPC), flavonoid content and total antioxidant capacity (TAC) through six different assay methods from twenty seven different varieties of pulses and split pulses commonly consumed in India. TPC and flavonoid content ranged between 38.6-542.7 mg GAE/100 g and 18.3-344.7 mg RE/100 g respectively. TAC measured by FRAP (90.6-2773.5 mg TE/100 g), RPA (190.8-2128.4 mg TE/100 g), DPPH radical scavenging assay (RSA) (42.9-571.1 mg TE/100 g), ABTS RSA (4.5-194.9 mg TE/100 g), hydroxyl RSA (0.0-106.6 mg AAE/g) and nitric oxide (NO) RSA (11.9-43.7 mg AAE/100 g) varied widely among pulses and split pulses analysed in the present study. TAC measured using different methods showed positively strong and significant correlation with TPC as well as flavonoid content except NORSA, indicating that phenolic compounds are the major contributors to the antioxidant properties of these plants. Food composition data obtained in this study would enrich the composition database at global level, which in turn will guide in improving food and nutrition security of the population. These can be used for further research, diet formulation and epidemiological studies. From the results it can be concluded that cow pea (red, small) had the highest TPC and TAC measured by all the parameters except NORSA.

Nesfatin-1 inhibits proliferation and enhances apoptosis of human adrenocortical H295R cells

NUCB2/nesfatin and its proteolytically cleaved product nesfatin-1 are recently discovered anorexigenic hypothalamic neuroproteins involved in energy homeostasis. It is expressed both centrally and in peripheral tissues, and appears to have potent metabolic actions. NUCB2/nesfatin neurons are activated in response to stress. Central nesfatin-1 administration elevates circulating ACTH and corticosterone levels. Bilateral adrenalectomy increased NUCB2/nesfatin mRNA levels in rat paraventricular nuclei. To date, studies have not assessed the effects of nesfatin-1 stimulation on human adrenocortical cells. Therefore, we investigated the expression and effects of nesfatin-1 in a human adrenocortical cell model (H295R). Our findings demonstrate that NUCB2 and nesfatin-1 are expressed in human adrenal gland and human adrenocortical cells (H295R). Stimulation with nesfatin-1 inhibits the growth of H295R cells and promotes apoptosis, potentially via the involvement of Bax, BCL-XL and BCL-2 genes as well as ERK1/2, p38 and JNK1/2 signalling cascades. This has implications for understanding the role of NUCB2/nesfatin in adrenal zonal development. NUCB2/nesfatin may also be a therapeutic target for adrenal cancer. However, further studies using in vivo models are needed to clarify these concepts.

Evaluation of cranial capacity by mustard seed technique

The volume of the cranium is used as a rough indicator of the size of the brain. In the present study Breitinger's mustard seeds technique was applied for the measurement of cranial capacity. Grossly normal 75 male skulls of Gujarat population were studied at Kesar SAL Medical College, Ahmedabad (Gujarat) in the year 2010. The mean cranial capacity among the study group was recorded to be 1256 cc with a minimum of 1110 cc and maximum of 1430 cc. The results were compared with the similar studies by different authors from different geographical areas.

G-protein coupled estrogen receptor 1 expression in rat and human heart: Protective role during ischaemic stress

G-protein coupled estrogen receptor 1, GPER, formerly known as GPR30, is a seven transmembrane domain receptor that mediates rapid estrogen responses in a wide variety of cell types. To date, little is known about the role of GPER during ischaemia/reperfusion injury. In this study, we report both mRNA and protein expression of GPER in the rat and human heart. The role of GPER in estrogen protection against ischaemic stress in the rat heart was also assessed using the isolated Langendorff system. Pre-treatment with 17beta-estradiol (E2) significantly decreased infarct size, (61.48+/-2.2% to 27.92+/-2.9% (P<0.001). Similarly, treatment with the GPER agonist G1 prior to 30-min global ischaemia followed by 120-min reperfusion significantly reduced infarct size from 61.48+/-2.2% to 23.85+/-3.2% (P<0.001), whilst addition of GPR30 antibody, abolished the protective effect of G1 (infarct size: 55.42+/-1.3%). The results suggest that GPER under cardiac stress exerts direct protection in the heart and may serve as a potential therapeutic target for cardiac drug therapy.

Application of peanut butter to improve fatty acid composition of biscuits

Biscuits prepared with different levels of hydrogenated fat (vanaspati) and peanut (Arachis hypogaea L.) butter (PB) (100:00, 75:25, 50;50, 25;75, 00:100) were evaluated for their fatty acid composition and textural property. Saturated fatty acids like myristic, palmitic, stearic acids were higher in control biscuits (100% vanaspati), which decreased with increasing proportion of PB in the experimental biscuits. Oleic acid and linoleic acid were lowest in control biscuits and it gradually increased upon incorporation of PB. The hardness of biscuits also increased with increasing proportion of PB. Overall sensory quality of experimental biscuits improved when 50% vanaspati replaced by PB in the standard biscuits recipe. Biscuits prepared with 50% supplementation of PB had better fatty acid composition with balanced oil quality and also had a greater acceptability by sensory evaluation panel.

Direct evidence of nitric oxide release from neuronal nitric oxide synthase activation in the left ventricle as a result of cervical vagus nerve stimulation

Information regarding vagal innervation in the cardiac ventricle is limited and the direct effect of vagal stimulation on ventricular myocardial function is controversial. We have recently provided indirect evidence that the anti-fibrillatory effect of vagus nerve stimulation on the ventricle is mediated by nitric oxide (NO). The aim of this study was to provide direct evidence for the release of nitric oxide in the cardiac ventricle during stimulation of the efferent parasympathetic fibres of the cervical vagus nerve. The isolated innervated rabbit heart was employed with the use of the NO fluorescent indicator 4,5-diaminofluorescein diacetate (DAF-2 DA) during stimulation of the cervical vagus nerves and acetylcholine perfusion in the absence and presence of the non-specific NO synthase inhibitor NG-nito-L-arginine (L-NNA) and the neuronal NO synthase selective inhibitor 1-(2-trifluormethylphenyl)imidazole (TRIM). Using the novel fluorescence method in the beating heart, we have shown that NO-dependent fluorescence is increased by 0.92 +/- 0.26, 1.20 +/- 0.30 and 1.91 +/- 0.27% (during low, medium and high frequency, respectively) in the ventricle in a stimulation frequency-dependent manner during vagus nerve stimulation, with comparable increases seen during separate stimulation of the left and right cervical vagus nerves. Background fluorescence is reduced during perfusion with L-NNA and the increase in fluorescence during high frequency vagal stimulation is inhibited during perfusion with both L-NNA (1.97 +/- 0.35% increase before L-NNA, 0.00 +/- 0.02% during L-NNA) and TRIM (1.78 +/- 0.18% increase before TRIM, -0.11 +/- 0.08% during TRIM). Perfusion with 0.1 microM acetylcholine increased NO fluorescence by 0.76 +/- 0.09% which was blocked by L-NNA (change of 0.00 +/- 0.03%) but not TRIM (increase of 0.82 +/- 0.21%). Activation of cardiac parasympathetic efferent nerve fibres by stimulation of the cervical vagus is associated with NO production and release in the ventricle of the rabbit, via the neuronal isoform of nitric oxide synthase.

A novel method of measuring nitric-oxide-dependent fluorescence using 4,5-diaminofluorescein (DAF-2) in the isolated Langendorff-perfused rabbit heart

4,5-Diaminofluorescein (DAF-2) has been used to measure nitric oxide (NO) activity from a variety of preparations. The aim of this study was to develop a method to assess changes in NO fluorescence using DAF-2 in isolated rabbit hearts (2.0-2.5 kg, n = 8). Hearts were perfused in constant flow Langendorff mode and instrumented to record aortic perfusion pressure, left ventricular pressure and left ventricular epicardial fluorescence using a bifurcated light guide at excitation wavelengths of 470 +/- 10, 480 +/- 10, 490 +/- 10 and 500 +/- 10 nm collected at 535 nm. DAF-2 DA was loaded using a single bolus 150-microl (1 micromol) injection. Changes in NO-dependent fluorescence were determined using the NO donor sodium nitroprusside (SNP: 100 microM), NO-dependent vasodilator bradykinin (BK: 100 microM) and non-specific NO synthase inhibitor NG-nitro-L-arginine (LNA: 200 microM) before and after loading hearts with DAF-2 DA. Before loading, these agents did not alter epicardial fluorescence. After loading, SNP, BK and LNA produced a consistent change in each excitation wavelength. Together, this suggests that change in fluorescence represents changes in the level of NO. SNP and BK increased whilst LNA significantly decreased left ventricular epicardial NO-dependent fluorescence. At the excitation wavelength of 490 nm, SNP and BK increased fluorescence by 104.7 +/- 18.7 mV (1.1 +/- 0.2%) and 150.7 +/- 26.1 mV (1.5 +/- 0.3%) respectively, whilst LNA significantly decreased fluorescence by 90.3 +/- 17.0 mV (-0.9 +/- 0.2%). Changing the rate of aortic perfusion did not alter fluorescence suggesting that changes in aortic perfusion pressure per se do not contribute to the changes in DAF-2 fluorescence seen with SNP, BK or LNA. Our data suggest that DAF-2 DA is a useful fluorescence indicator for measuring NO activity in isolated hearts.

Nitric oxide mediates the vagal protective effect on ventricular fibrillation via effects on action potential duration restitution in the rabbit heart

We have previously shown that direct vagus nerve stimulation (VNS) reduces the slope of action potential duration (APD) restitution while simultaneously protecting the heart against induction of ventricular fibrillation (VF) in the absence of any sympathetic activity or tone. In the current study we have examined the role of nitric oxide (NO) in the effect of VNS. Monophasic action potentials were recorded from a left ventricular epicardial site on innervated, isolated rabbit hearts (n = 7). Standard restitution, effective refractory period (ERP) and VF threshold (VFT) were measured at baseline and during VNS in the presence of the NO synthase inhibitor N(G)-nitro-L-arginine (L-NA, 200 microm) and during reversing NO blockade with L-arginine (L-Arg, 1 mm). Data represent the mean +/- S.E.M. The restitution curve was shifted upwards and became less steep with VNS when compared to baseline. L-NA blocked the effect of VNS whereas L-Arg restored the effect of VNS. The maximum slope of restitution was reduced from 1.17 +/- 0.14 to 0.60 +/- 0.09 (50 +/- 5%, P < 0.0001) during control, from 0.98 +/- 0.14 to 0.93 +/- 0.12 (2 +/- 10%, P = NS) in the presence of L-NA and from 1.16 +/- 0.17 to 0.50 +/- 0.10 (41 +/- 9%, P = 0.003) with L-Arg plus L-NA. ERP was increased by VNS in control from 119 +/- 6 ms to 130 +/- 6 ms (10 +/- 5%, P = 0.045) and this increase was not affected by L-NA (120 +/- 4 to 133 +/- 4 ms, 11 +/- 3%, P = 0.0019) or L-Arg with L-NA (114 +/- 4 to 123 +/- 4 ms, 8 +/- 2%, P = 0.006). VFT was increased from 3.0 +/- 0.3 to 5.8 +/- 0.5 mA (98 +/- 12%, P = 0.0017) in control, 3.4 +/- 0.4 to 3.8 +/- 0.5 mA (13 +/- 12%, P = 0.6) during perfusion with L-NA and 2.5 +/- 0.4 to 6.0 +/- 0.7 mA (175 +/- 50%, P = 0.0017) during perfusion with L-Arg plus L-NA. Direct VNS increased VFT and flattened the slope of APD restitution curve in this isolated rabbit heart preparation with intact autonomic nerves. These effects were blocked using L-NA and reversed by replenishing the substrate for NO production with L-Arg. This is the first study to demonstrate that NO plays an important role in the anti-fibrillatory effect of VNS on the rabbit ventricle, possibly via effects on APD restitution.

Autonomic modulation of electrical restitution, alternans and ventricular fibrillation initiation in the isolated heart

OBJECTIVE

Abnormal autonomic nerve activity is a strong prognostic marker for ventricular arrhythmias but the mechanisms underlying the autonomic modulation of ventricular fibrillation (VF) initiation are poorly understood. We examined the effects of direct sympathetic (SS) and vagus (VS) nerve stimulation on electrical restitution, alternans and VF threshold (VFT) in a novel isolated rabbit heart preparation with intact dual autonomic innervation.

METHODS

Monophasic Action Potentials (MAPs) were recorded from a left ventricular epicardial site on innervated, isolated rabbit hearts (n=16). Standard restitution, effective refractory period (ERP), electrical alternans and VFT were measured at baseline and during SS and VS separately.

RESULTS

The restitution curve was shifted downwards and made steeper with SS whilst VS caused an upward shift and a flattening of the curve. The maximum slope of restitution was increased from 1.30+/-0.10 at baseline to 1.86+/-0.17 (by 45+/-12%, P<0.01) with SS and decreased to 0.69+/-0.10 (by 51+/-6%, P<0.001) with VS. ERP was decreased from 127.3+/-2.5 ms to 111.8+/-1.8 ms with SS (by 12+/-2%, P<0.001) and increased to 144.0+/-2.2 ms with VS (by 13+/-2%, P<0.001). VFT was decreased from 4.7+/-0.6 mA to 1.9+/-0.5 mA with SS (by 64+/-5%, P<0.001) and increased to 8.7+/-1.1 mA with VS (by 89+/-14%, P<0.0005). There was a significant inverse relationship between the maximum slope of restitution and VFT (r=-0.63, P<0.0001). When compared with baseline, SS caused electrical alternans at longer pacing cycle lengths (139.0+/-8.4 vs. 123.0+/-7.8 ms, P<0.01) with greater degree of alternans (32.5+/-9.9 vs. 15.4+/-3.2%, P<0.05). It also caused a wider range of cycle lengths where alternans occurred (53.0+/-6.2 vs. 41.0+/-7.0 ms, P<0.05) whilst vagus nerve stimulation shortened this range (33.0+/-7.3 ms, P<0.001).

CONCLUSIONS

Sympathetic stimulation increased maximum slope of restitution and electrical alternans but decreased ERP and VF threshold whilst vagus nerve stimulation had opposite effects. The interaction between action potential duration and beat-to-beat interval may play an important role in the autonomic modulation of VF initiation.

MR imaging of the female pelvis: current perspectives and review of genital tract congenital anomalies, and benign and malignant diseases

MR imaging continues to be an integral problem-solving modality in the evaluation of congenital anomalies and acquired diseases of the female genital tract organs and provides effective clinical information to the practicing gynecologist in those patients in whom sonography is technically suboptimal or the results are equivocal. This article describes the state-of-the art MR imaging of the female pelvis and addresses its current perspectives in the following sections: (1) technical aspects of MR in imaging the female pelvis, (2) normal pelvic anatomy and variations that are seen on MRI, (3) role of MRI in the diagnosis of congenital uterine and vaginal anomalies, (4) MR imaging approach to diagnose congenital uterine and vaginal anomalies, (5) advantages and limitations of MR in the evaluation of various benign diseases and malignant neoplasms of the female genital tract, (6) a MR staging system and criteria for each gynecologic malignancy, (7) fundamental MR criteria to differentiate benign from malignant tumors and recurrent tumors from fibrosis, and (8) the present cost-effective value of MR in pregnancy and obstetrics. Magnetic resonance (MR) technology continues to be an important problem-solving modality in the evaluation of benign, malignant, and recurrent diseases of the female pelvic organs with the development of new software and improved hardware over the last few years. The main issues addressed in this article are (1) to review the basic and expanded applications of the current state-of-the art MR imaging in the diagnosis and management of various congenital and acquired disorders of the female pelvic organs, (2) to illustrate a simplified clinico-radiologic (MRI) approach to the diagnosis of congenital and acquired pathologies of the pelvic organs, (3) to provide relevant information to the clinicians to make rational choices among the competing imaging modalities, and (4) to outline the future potential of this modality in the pelvis.

Normal variation in MRI of the brain

Compared with CT, much more detail and information is seen on any standard MRI sequence. The task of reviewing MRI head scans can therefore be daunting to the new radiologist. This article outlines and emphasizes many of the predictable normal variants, hopefully lessening the burden and preventing the reader from misidentifying many of the common structures.

Multiple reflective channels in the spleen: a sonographic sign of portal hypertension

We consistently observed small "reflective channels" (RCs) in the splenic parenchyma in patients with portal hypertension (PHT). The purpose of this study was to investigate the frequency of this sign in PHT and in splenic disorders unrelated to PHT compared to normal controls. The significance of this sign in the diagnosis of PHT and in differentiating PHT splenomegalies from others was also assessed. A total of 337 patients underwent sonographic examination of the spleen: 147 normal, 75 non-PHT splenic pathologies, and 115 with PHT. The RCs were scored from grade 0 to 3 by counting the number in an area of 12 mm2 in the splenic parenchyma. Of 222 normal and non-PHT spleens, 174 (78%) showed grade 0, 44 (20%) grade 1, four grade 2 (1%), and none showed grade 3 RCs. Of 115 PHT cases, 17 showed grade 0, 25 grade 1, 44 grade 2, and 29 showed grade 3 RCs. The sensitivity of this sign was 0.85 with a specificity of 0.77 and an accuracy of 0.80 in detecting PHT (p < 0.001). The interobserver and intraobserver variation for grading was insignificant (p > 0.1). The RCs could be explained by periarterial fibrosis and dilatation of venous sinuses with increased collagen in their walls, which is known to occur in PHT. The vascular nature on ultrasound (US) was confirmed by the presence of flow on color Doppler. This sign is readily differentiated from the calcifications of tuberculosis, histoplasmosis, sickle cell infarcts, and phleboliths; it serves as a useful aid in diagnosing and differentiating PHT splenomegaly from non-PHT splenomegaly.

Ureteral obstruction in hydatid disease

A case of ureteric obstruction in renal hydatid disease is reported. This unusual complication possibly occurred following surgery. To the best of our knowledge, this has not been previously reported.

Ultrasound guided aspiration cytology--a valuable diagnostic aid

Ultrasonography (US) remains underutilized as a guidance tool for performing fine needle aspiration cytology (FNAC) mainly because of a lack of understanding and experience in this technique. We describe here our experience in performing 346 FNACs. In our opinion, US guided FNACs are highly accurate and safe procedures which can be done on an out-patient basis, with routinely available equipment.