scholarly journals Peripherally injected ghrelin and leptin reduce food hoarding and mass gain in the coal tit ( Periparus ater )

2018 ◽  
Vol 285 (1879) ◽  
pp. 20180417 ◽  
Author(s):  
Lindsay J. Henderson ◽  
Rowan C. Cockcroft ◽  
Hiroyuki Kaiya ◽  
Timothy Boswell ◽  
Tom V. Smulders
Keyword(s):  
Food Consumption ◽  
Hormonal Regulation ◽  
Mass Gain ◽  
Hormonal Control ◽  
Avian Species ◽  
Nutritional State ◽  
Saline Control ◽  
High Dose ◽  
Food Hoarding ◽  
Coal Tit

In birds little is known about the hormonal signals that communicate nutritional state to the brain and regulate appetitive behaviours. In mammals, the peptide hormones ghrelin and leptin elevate and inhibit consumption and food hoarding, respectively. But in birds, administration of both ghrelin and leptin inhibit food consumption. The role of these hormones in the regulation of food hoarding in avian species has not been examined. To investigate this, we injected wild caught coal tits ( Periparus ater ) with leptin, high-dose ghrelin, low-dose ghrelin and a saline control in the laboratory. We then measured food hoarding and mass gain, as a proxy of food consumption, every 20 min for 2 h post-injection. Both high-dose ghrelin and leptin injections significantly reduced hoarding and mass gain compared with controls. Our results provide the first evidence that hoarding behaviour can be reduced by both leptin and ghrelin in a wild bird. These findings add to evidence that the hormonal control of food consumption and hoarding in avian species differs from that in mammals. Food hoarding and consumptive behaviours consistently show the same response to peripheral signals of nutritional state, suggesting that the hormonal regulation of food hoarding has evolved from the consumption regulatory system.

scholarly journals Role of spinal GABAA receptors in pudendal inhibition of nociceptive and nonnociceptive bladder reflexes in cats

2014 ◽  
Vol 306 (7) ◽  
pp. F781-F789 ◽  
Author(s):  
Zhiying Xiao ◽  
Jeremy Reese ◽  
Zeyad Schwen ◽  
Bing Shen ◽  
Jicheng Wang ◽  
...  
Keyword(s):  
Gabaa Receptors ◽  
Bladder Capacity ◽  
Aminobutyric Acid ◽  
Saline Control ◽  
Receptor Subtype ◽  
High Dose ◽  
Multiple Threshold ◽  
Bladder Activity ◽  
Subtype A

Picrotoxin, an antagonist for γ-aminobutyric acid receptor subtype A (GABAA), was used to investigate the role of GABAA receptors in nociceptive and nonnociceptive reflex bladder activities and pudendal inhibition of these activities in cats under α-chloralose anesthesia. Acetic acid (AA; 0.25%) was used to irritate the bladder and induce nociceptive bladder overactivity, while saline was used to distend the bladder and induce nonnociceptive bladder activity. To modulate the bladder reflex, pudendal nerve stimulation (PNS) was applied at multiple threshold (T) intensities for inducing anal sphincter twitching. AA irritation significantly ( P < 0.01) reduced bladder capacity to 34.3 ± 7.1% of the saline control capacity, while PNS at 2T and 4T significantly ( P < 0.01) increased AA bladder capacity to 84.0 ± 7.8 and 93.2 ± 15.0%, respectively, of the saline control. Picrotoxin (0.4 mg it) did not change AA bladder capacity but completely removed PNS inhibition of AA-induced bladder overactivity. Picrotoxin (iv) only increased AA bladder capacity at a high dose (0.3 mg/kg) but significantly ( P < 0.05) reduced 2T PNS inhibition at low doses (0.01–0.1 mg/kg). During saline cystometry, PNS significantly ( P < 0.01) increased bladder capacity to 147.0 ± 7.6% at 2T and 172.7 ± 8.9% at 4T of control capacity, and picrotoxin (0.4 mg it or 0.03–0.3 mg/kg iv) also significantly ( P < 0.05) increased bladder capacity. However, picrotoxin treatment did not alter PNS inhibition during saline infusion. These results indicate that spinal GABAA receptors have different roles in controlling nociceptive and nonnociceptive reflex bladder activities and in PNS inhibition of these activities.

scholarly journals Polyphenol-Rich Purple Corn Pericarp Extract Adversely Impacts Herbivore Growth and Development

Insects ◽  
2020 ◽  
Vol 11 (2) ◽  
pp. 98 ◽  
Author(s):  
Mandeep Tayal ◽  
Pavel Somavat ◽  
Isabella Rodriguez ◽  
Tina Thomas ◽  
Bradley Christoffersen ◽  
...  
Keyword(s):  
Hormonal Regulation ◽  
Growth And Development ◽  
Control Diet ◽  
Insect Pest ◽  
Plant Secondary Metabolites ◽  
Mass Gain ◽  
Developmental Time ◽  
Egg Hatching ◽  
Indirect Defenses ◽  
Purple Corn

Plant secondary metabolites such as terpenes, phenolics, glycosides, and alkaloids play various functional roles including pigmentation, foliar and floral volatile synthesis, hormonal regulation, and direct and indirect defenses. Among these, phenolic compounds are commonly found in plants, but vary in the distribution of their specific compounds among plant families. Polyphenols, including anthocyanins and tannins, are widely distributed and have been well documented for their roles- primarily in plant pigmentation and also in plant defenses. However, commercialization of such compounds for use in insect pest management is severely hampered by expensive, inefficient, and time-consuming extraction protocols. Using a recently developed inexpensive and easy extraction method using the byproducts of pigmented (purple) corn processing, we examined whether the crude pericarp extract rich in polyphenols can affect the growth and development of tobacco hornworm (Manduca sexta L.) caterpillars. Our findings show that purple corn pericarp extract negatively affected M. sexta egg hatching and larval mass gain and prolonged developmental time compared to regular yellow corn extract or an artificial control diet. We also found that these effects were more severe during the early stages of caterpillar development. These results conclusively demonstrate that purple corn pericarp, an inexpensive by-product of the corn milling industry, is a valuable product with excellent potential as an insect antifeedant.

Effect of continuous infusions of CCK-8 on food intake and body and pancreatic weights in rats

1988 ◽  
Vol 254 (1) ◽  
pp. R17-R22 ◽  
Author(s):  
L. Lukaszewski ◽  
M. Praissman
Keyword(s):  
Food Intake ◽  
Food Consumption ◽  
High Dose ◽  
Weight Changes ◽  
Body Weight Changes ◽  
Jugular Veins ◽  
Indirect Measure ◽  
Pancreatic Growth ◽  
Infusion Period

The ability of cholecystokinin (CCK) to act as a long-term satiety factor was assessed by its continuous infusion into the jugular veins of rats. Animals receiving a low dose of cholecystokinin octapeptide (CCK-8) (0.6 microgram CCK-8.kg body wt-1.h-1) did not show any significant differences in body weight changes or in food consumption from rats receiving saline and a group of unoperated controls over the 7-day infusion period. A 19.3-fold greater dose of CCK-8 (11.6 micrograms.kg body wt-1.h-1) did cause a significant decline in food consumption for the first 4 days compared with saline-infused rats (P less than 0.05) and unoperated controls (P less than 0.01). Rats receiving a high dose of CCK gained weight at a slower rate than rats receiving saline, but this effect lasted only 2 days and was not significant. Pancreatic growth was used as an indirect measure of elevated CCK levels in these animals. The infusion of 0.6 microgram CCK-8.kg body wt-1.h-1 did not lead to sufficiently elevated peptide levels to promote pancreatic growth. In contrast, those rats receiving a high dose of CCK-8 had significantly greater pancreatic weights (P less than 0.01) compared with saline-treated rats and unoperated controls. These results indicate that CCK-8, when administered continuously and in a large enough dose, can suppress food intake in rats for a period of several days before losing its effectiveness.

scholarly journals Hormonal regulation of thirst in the amphibious ray-finned fish suggests the requirement for terrestrialization during evolution

2019 ◽  
Vol 9 (1) ◽  
Author(s):  
Yukitoshi Katayama ◽  
Yoshio Takei ◽  
Makoto Kusakabe ◽  
Tatsuya Sakamoto
Keyword(s):  
Angiotensin Ii ◽  
Atrial Natriuretic Peptide ◽  
Natriuretic Peptide ◽  
Neural Activity ◽  
Related Species ◽  
Hormonal Regulation ◽  
Hormonal Control ◽  
Intracerebroventricular Injection ◽  
Drinking Rate ◽  
Swallowing Reflex

Abstract Thirst has evolved for vertebrate terrestrial adaptation. We previously showed that buccal drying induced a series of drinking behaviours (migration to water–taking water into the mouth–swallowing) in the amphibious mudskipper goby, thereby discovering thirst in ray-finned fish. However, roles of dipsogenic/antidipsogenic hormones, which act on the thirst center in terrestrial tetrapods, have remained unclear in the mudskipper thirst. Here we examined the hormonal effects on the mudskipper drinking behaviours, particularly the antagonistic interaction between angiotensin II (AngII) and atrial natriuretic peptide (ANP) which is important for thirst regulation in mammalian ‘forebrain’. Expectedly, intracerebroventricular injection of ANP in mudskippers reduced AngII-increased drinking rate. ANP also suppressed the neural activity at the ‘hindbrain’ region for the swallowing reflex, and the maintenance of buccopharyngeal water due to the swallowing inhibition may attenuate the motivation to move to water. Thus, the hormonal molecules involved in drinking regulation, as well as the influence of buccopharyngeal water, appear to be conserved in distantly related species to solve osmoregulatory problems, whereas hormonal control of thirst at the forebrain might have been acquired only in tetrapod lineage during evolution.

scholarly journals Subchronic Oral Toxicity Study of Decitabine in Combination With Tetrahydrouridine in CD-1 Mice

2014 ◽  
Vol 33 (2) ◽  
pp. 75-85 ◽  
Author(s):  
Pramod Terse ◽  
Kory Engelke ◽  
Kenneth Chan ◽  
Yonghua Ling ◽  
Douglas Sharpnack ◽  
...  
Keyword(s):  
Bone Marrow ◽  
Combination Therapy ◽  
Food Consumption ◽  
Blood Cells ◽  
Recovery Period ◽  
White Blood Cells ◽  
Clinical Pathology ◽  
High Dose ◽  
Severe Toxicity ◽  
Oral Toxicity

Decitabine (5-aza-2′-deoxycytidine; DAC) in combination with tetrahydrouridine (THU) is a potential oral therapy for sickle cell disease and β-thalassemia. A study was conducted in mice to assess safety of this combination therapy using oral gavage of DAC and THU administered 1 hour prior to DAC on 2 consecutive days/week for up to 9 weeks followed by a 28-day recovery to support its clinical trials up to 9-week duration. Tetrahydrouridine, a competitive inhibitor of cytidine deaminase, was used in the combination to improve oral bioavailability of DAC. Doses were 167 mg/kg THU followed by 0, 0.2, 0.4, or 1.0 mg/kg DAC; THU vehicle followed by 1.0 mg/kg DAC; or vehicle alone. End points evaluated were clinical observations, body weights, food consumption, clinical pathology, gross/histopathology, bone marrow micronuclei, and toxicokinetics. There were no treatment-related effects noticed on body weight, food consumption, serum chemistry, or urinalysis parameters. Dose- and gender-dependent changes in plasma DAC levels were observed with a Cmax within 1 hour. At the 1 mg/kg dose tested, THU increased DAC plasma concentration (∼10-fold) as compared to DAC alone. Severe toxicity occurred in females receiving high-dose 1 mg/kg DAC + THU, requiring treatment discontinuation at week 5. Severity and incidence of microscopic findings increased in a dose-dependent fashion; findings included bone marrow hypocellularity (with corresponding hematologic changes and decreases in white blood cells, red blood cells, hemoglobin, hematocrit, reticulocytes, neutrophils, and lymphocytes), thymic/lymphoid depletion, intestinal epithelial apoptosis, and testicular degeneration. Bone marrow micronucleus analysis confirmed bone marrow cytotoxicity, suppression of erythropoiesis, and genotoxicity. Following the recovery period, a complete or trend toward resolution of these effects was observed. In conclusion, the combination therapy resulted in an increased sensitivity to DAC toxicity correlating with DAC plasma levels, and females are more sensitive compared to their male counterparts.

scholarly journals Long-chain SFA at thesn-1, 3 positions of TAG reduce body fat deposition in C57BL/6 mice

2013 ◽  
Vol 110 (11) ◽  
pp. 1987-1995 ◽  
Author(s):  
Shiou Wah Gouk ◽  
Sit Foon Cheng ◽  
Josephine Shiueh Lian Mok ◽  
Augustine Soon Hock Ong ◽  
Cheng Hock Chuah
Keyword(s):  
Food Consumption ◽  
Body Fat ◽  
Positional Distribution ◽  
Subcutaneous Fat ◽  
Mass Gain ◽  
Fat Deposition ◽  
Fat Accretion ◽  
Total Fat ◽  
Similar Body ◽  
Long Chain

The present study aimed to determine the effect of positional distribution of long-chain SFA in TAG, especially at thesn-1, 3 positions, on fat deposition using the C57BL/6 mouse model. Throughout the 15 weeks of the study, mice were fed with diets fortified with palm olein (POo), chemically interesterified POo (IPOo) and soyabean oil (SOY). Mice receiving the SOY-enriched diet gained significantly higher amounts of subcutaneous fat (P= 0·011) and total fat (P= 0·013) compared with the POo group, despite similar body mass gain being recorded. During normalisation with food consumption to obtain the fat:feed ratio, mice fed with the POo-enriched diet exhibited significantly lower visceral (P= 0·044), subcutaneous (P= 0·006) and total (P= 0·003) fat:feed than those fed with the SOY-enriched diet. It is noteworthy that mice fed with the IPOo-enriched diet gained 14·3 % more fat per food consumed when compared with the POo group (P= 0·013), despite their identical total fatty acid compositions. This was mainly attributed to the higher content of long-chain SFA at thesn-1, 3 positions of TAG in POo, which results in delayed absorption after deacylation as evidenced by the higher amounts of long-chain SFA excreted in the faeces of mice fed with the POo-enriched diet. Negative correlations were found between the subcutaneous, visceral as well as total fat accretion per food consumption and the total SFA content at thesn-1, 3 positions, while no relationships were found for MUFA and PUFA. The present results show that the positional distribution of long-chain SFA exerts a more profound effect on body fat accretion than the total SFA content.

Regulation of the immunoexpression of aquaporin 9 by ovarian hormones in the rat oviductal epithelium

2005 ◽  
Vol 288 (5) ◽  
pp. C1048-C1057 ◽  
Author(s):  
María C. Brañes ◽  
Bernardo Morales ◽  
Mariana Ríos ◽  
Manuel J. Villalón
Keyword(s):  
Steroid Hormones ◽  
Estrous Cycle ◽  
Hormonal Regulation ◽  
Water Movement ◽  
Water Channels ◽  
Hormonal Control ◽  
Apical Plasma Membrane ◽  
Functional Assay ◽  
Mrna Levels ◽  
Oviductal Epithelium

The volume of oviductal fluid fluctuates during the estrous cycle, suggesting that water availability is under hormonal control. It has been postulated that sex-steroid hormones may regulate aquaporin (AQP) channels involved in water movement across cell membranes. Using a functional assay (oocytes of Xenopus laevis), we demonstrated that the rat oviductal epithelium contains mRNAs coding for water channels, and we identified by RT-PCR the mRNAs for AQP5, -8, and -9, but not for AQP2 and -3. The immunoreactivity for AQP5, -8, and -9 was localized only in epithelial cells of the oviduct. The distribution of AQP5 and -8 was mainly cytoplasmic, whereas we confirmed, by confocal microscopy, that AQP9 localized to the apical plasma membrane. Staining of AQP5, -8, and -9 was lost after ovariectomy, and only AQP9 immunoreactivity was restored after estradiol and/or progesterone treatments. The recovery of AQP9 reactivity after ovariectomy correlated with increased mRNA and protein levels after treatment with estradiol alone or progesterone administration after estradiol priming. Interestingly, progesterone administration after progesterone priming also induced AQP9 expression but without a change in mRNA levels. Levels of AQP9 varied along the estrous cycle with their highest levels during proestrus and estrus. These results indicate that steroid hormones regulate AQP9 expression at the mRNA and protein level and that other ovarian signals are involved in the expression of AQP5 and -8. Thus hormonal regulation of the type and quantity of water channels in this epithelium might control water transport in the oviductal lumen.

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