Clinical application of ghrelin in the field of surgery

Cachexia Index in Patients with Gastrointestinal Cancer: A Systematic Review and Meta-Analysis

PURPOSE

The cachexia index is a novel biomarker of cancer cachexia. This systematic review and meta-analysis aimed to evaluate the prognostic impact of cachexia index on prognosis after surgery for gastrointestinal cancer.

METHODS

In August 2023, we systematically searched PubMed, the Cochrane Library, and Ovid for relevant studies on the oncological outcome after gastrointestinal cancer surgery and analyzed the findings from these studies for meta-analysis.

RESULTS

Our systematic and meta-analysis review identified eight studies involving 1876 patients. The number of patients with low cachexia index accounted for 813 patients (43.3%). We found that low cachexia index was associated with worse overall survival (pooled HR, 2.30; 95% CI, 1.85-2.87; z = 7.49; P < 0.001) and disease/relapse/progression-free survival (pooled HR, 1.77; 95% CI, 1.45-2.18; z = 5.50; P < 0.001).

CONCLUSION

Our meta-analysis showed that cachexia index was associated with oncological outcome after gastrointestinal cancer surgery. However, the limitations of this meta-analysis should be taken into consideration when interpreting the results.

Oncological relevance of proximal gastrectomy in advanced gastric cancer of upper third of the stomach

Background

The oncological relevance of proximal gastrectomy in advanced gastric cancer remains unclear. We aimed to examine the frequency of lymph node metastasis in advanced gastric cancer to determine the oncological validity of proximal gastrectomy selection.

Materials and methods

This study included consecutive 71 patients with locally advanced gastric cancer in the upper third of the stomach who underwent total gastrectomy at our institution between 2001 and 2017. Lymph node metastasis and its therapeutic value index were examined to identify candidates for proximal gastrectomy. Metastatic and 3-year overall survival rates of numbers 3a and 3b lymph nodes were examined from 2010 to 2019.

Results

The metastatic rate and therapeutic value index of numbers 4d, 5, 6, and 12a lymph nodes were zero or low. The number 3 lymph node had a metastatic rate and therapeutic value index of 36.6 % and 31.1, respectively. The metastatic and 3-year overall survival rates of the number 3a lymph node were 32.7 % and 89 %, respectively, whereas those of the number 3b lymph node were 3.8 % and 100 %, respectively. All patients with positive metastasis to the number 3b lymph node received adjuvant chemotherapy. Histopathological findings of positive metastasis to the number 3b lymph node were located in the lesser curvature, and the tumor diameter exceeded 40 mm.

Conclusion

For advanced gastric cancer of the upper third of the stomach, the indications of localization to the lesser curvature and a tumor diameter of >40 mm should be considered cautiously.

Prognostic significance of the cachexia index in patients with stage I-III colorectal cancer who underwent laparoscopic surgery

PURPOSE

The prognostic significance of the cachexia index, a novel biomarker of cancer cachexia, remains unclear in colorectal cancer; we, therefore, evaluated this relationship.

METHODS

This retrospective cohort study included 306 patients with stage I-III colorectal cancer who underwent R0 resection between April 2010 and March 2020. The cachexia index was calculated as (skeletal muscle index [cm2/m2] × serum albumin level [g/dL])/neutrophil-to-lymphocyte ratio. The overall and disease-free survival rates were analyzed using a Cox proportional hazards model.

RESULTS

A low cachexia index was found in 94 patients. This group had significantly lower disease-free survival and overall survival than the high-cachexia index group (5-year survival, 86.3% vs. 63.1%, p < 0.01; 87.9% vs. 67.2%, p < 0.01). Multivariate analyses showed that T3 or T4 (hazard ratio [HR]: 2.56; 95% confidence interval CI 1.04-6.25, p = 0.039), stage III (HR: 3.77; 95% CI 1.79-7.93, p < 0.01), and a low cachexia index (HR: 2.27; 95% CI 1.31-3.90, p = 0.003) were significant independent predictors of the disease-free survival. CA19-9 ≥ 37.0 ng/mL (HR: 2.68; 95% CI: 1.37-5.24, p = 0.004), stage III (HR: 2.57; 95% CI 1.34-4.92, p = 0.004), and a low cachexia index (HR: 2.35; 95% CI 1.31-4.21, p = 0.004) were significant independent predictors of the overall survival.

CONCLUSION

A low cachexia index might be a long-term prognostic factor of colorectal cancer.

Body Composition Changes Following Sleeve Gastrectomy Vs. One-Anastomosis Gastric Bypass: Tehran Obesity Treatment Study (TOTS)

PURPOSE

This study aimed to evaluate body composition changes and the determinants of fat-free mass loss (FFML) up to 3 years after sleeve gastrectomy (SG) and one-anastomosis gastric bypass (OAGB).

MATERIALS AND METHODS

A prospective study was conducted on 3864 patients with severe obesity who underwent either SG (2746, 76.1% women, mean age: 39.2 ± 11.6 years, and BMI: 44.3 ± 5.6 kg/m2) or OAGB (1118, 82.2% women, age: 39.9 ± 10.7 years, BMI: 45.6 ± 6.3 kg/m2). Body composition parameters were measured by bioelectrical impedance analysis preoperatively and 1, 3, 6, 9, 12, 18, 24, and 36 months after surgery. Changes in body composition were assessed using the propensity matched generalized estimated equation (GEE) method. The determinants of fat-free mass loss/weight loss (FFML/WL%) were defined using a mixed-model GEE analysis.

RESULTS

Means of FM, FFM, and FFML/WL% decreased significantly in both study groups (Ptrend < 0.001). Changes in BMI, EWL%, FM, and FFML/WL% were different between the two groups (Pbetween < 0.05). The results showed a better FFM preservation and a greater FM loss over time in the OAGB group compared to the SG group (Pinteraction < 0.05). FFML during the first 3 months was greater in the SG compared to the OAGB group (P < 0.001). SG surgery, higher preoperative BMI, and female gender were associated with greater FFML/WL%.

CONCLUSION

In the SG compared to the OAGB group, FFML was greater, especially early after the surgery, emphasizing the need for therapeutic interventions such as regular exercise programs and dietary intake modifications.

The evaluation of the postoperative quality of life in patients undergoing radical gastrectomy for esophagogastric junction cancer using the Postgastrectomy Syndrome Assessment Scale-45: a nationwide multi-institutional study

PURPOSE

This retrospective nationwide survey investigated the quality of life (QOL) of patients with esophagogastric junction cancer after gastrectomy using the Postgastrectomy Syndrome Assessment Scale-45.

METHODS

The Postgastrectomy Syndrome Assessment Scale-45 comprises 45 questions classified into symptoms, living status, and QOL domains. A total of 1950 gastrectomized patients with upper-third gastric or esophagogastric junction cancer returned the completed forms. Among them, 224 eligible patients with esophagogastric junction cancer were selected, including 86, 120, and 18 patients who underwent total gastrectomy, proximal gastrectomy (reconstruction-esophagogastrostomy: 56; double-tract method: 51), and other procedures, respectively.

RESULTS

The postoperative period was significantly shorter (47 ± 30 vs. 34 ± 30 months, p = 0.002), and the rates of early-stage disease and minimally invasive approaches significantly higher (both p < 0.001) in the proximal gastrectomy group than in the total gastrectomy group. Despite advantageous background factors for proximal gastrectomy, the postoperative QOL did not differ markedly between the groups. Compared to patients who underwent reconstruction with the double-tract method, patients who underwent esophagogastrostomy had significantly larger remnant stomachs but a similar QOL.

CONCLUSION

Even with total gastrectomy, a postoperative QOL comparable to that with proximal gastrectomy can be maintained. Clarifying the optimal reconstruction methods for proximal gastrectomy for esophagogastric junction cancer is warranted.

TRIAL REGISTRATION

This study was registered at the University Hospital Medical Information Network Clinical Trials Registry (UMIN-CTR; registration number: 000032221).

Effects of Des-acyl Ghrelin on Insulin Sensitivity and Macrophage Polarization in Adipose Tissue

Background and Objectives

Obesity is the accumulation of adipose tissue caused by excess energy in the body, accompanied by long-term chronic low-grade inflammation of adipose tissue. More than 50% of interstitial cells in adipose tissue are macrophages, which produce cytokines closely related to insulin resistance. Macrophage biology is driven by two polarization phenotypes, M1 (proinflammatory) and M2 (anti-inflammatory). This study aimed to investigate the effect of gastric hormone des-acyl ghrelin (DAG) on the polarization phenotype of macrophages and elucidate the role of macrophages in adipose tissue inflammation and insulin sensitivity and its molecular mechanism.

Methods

Mice were subcutaneously administrated with DAG in osmotic minipumps. The mice were fed a normal diet or a high-fat diet (HFD). Different macrophage markers were detected by real-time revere transcription polymerase chain reaction.

Results

Exogenous administration of DAG significantly inhibited the increase of adipocyte volume caused by HFD and reduced the number of rosette-like structures in adipose tissue. HFD in the control group significantly increased M1 macrophage markers, tumor necrosis factor α (TNFα), and inducible NO synthase (iNOS). However, these increases were reduced or even reversed after DAG administration in vitro. The M2 markers, macrophage galactose type C-type Lectin-1 (MGL1), arginase 1 (Arg1), and macrophage mannose receptor 1 (MRC1) were decreased by HFD, and the downward trend was inhibited or reversed after DAG administration. Although Arg1 was elevated after HFD, the fold increase after DAG administration in vitro was much greater than that in the control group.

Conclusion

DAG inhibits adipose tissue inflammation caused by HFD, reduces infiltration of macrophages in adipose tissue, and promotes polarization of macrophages to M2, thus alleviating obesity and improving insulin sensitivity.

Administration of a standard dose of vonoprazan fumarate delays gastric emptying in Japanese healthy adults: a prospective clinical trial

BACKGROUND

There is no established view of how gastric acid suppression affects the time for gastric emptying. Vonoprazan fumarate shows potent and durable gastric acid inhibitory effects, but its effects on gastric emptying have not been studied widely. We investigated the effects of vonoprazan fumarate on gastric emptying and measured serum gastrin and plasma ghrelin levels in healthy adults.

METHODS

Ten participants were administered 10 mg vonoprazan fumarate daily for 14 days, then 20 mg vonoprazan fumarate daily for 14 days. The gastric emptying breath test was performed and serum gastrin levels were measured at baseline and after each medication administration period. The protocol was then repeated, with the gastric emptying breath test and serum gastrin and plasma desacyl-ghrelin levels measured at baseline and the end of the medication trial.

RESULTS

Mean serum gastrin levels increased in a dose-dependent manner [baseline: 104.7 ± 50.4, after 10 mg protocol: 328 ± 123.8, after 20 mg protocol: 555 ± 378.8 (pg/mL, mean ± standard deviation), p = 0.0008]. There was a significant difference between the gastric emptying breath test Tmax at baseline and just after the 20 mg protocol (baseline: 45.5 ± 15.3, after 20 mg protocol: 60.5 ± 19.6 min, p = 0.0418). Plasma desacyl-ghrelin levels increased significantly just after the 20 mg protocol compared to those at baseline [baseline: 222.3 ± 106.4, after 20 mg protocol: 366.2 ± 178.6 (fmol/mL), p = 0.0008].

CONCLUSIONS

In healthy adults, 14 days of vonoprazan fumarate administration at 20 mg/day delayed gastric emptying.

TRIAL REGISTRATION

This clinical trial was registered in the University hospital Medical Information Network Clinical Trial Registry (Trial No. UMIN000039199 and UMIN000042969).

Relationship between Orexigenic Peptide Ghrelin Signal, Gender Difference and Disease

Growth hormone secretagogue receptor 1a (GHS-R1a), which is one of the G protein-coupled receptors (GPCRs), is involved in various physiological actions such as energy consumption, growth hormone secretion promoting action, and cardiovascular protective action. The ligand was searched for as an orphan receptor for a while, but the ligand was found to be acylated ghrelin (ghrelin) discovered by Kangawa and Kojima et al. in 1999. Recently, it has also been reported that dysregulation of GHS-R1a mediates reduced feeding in various diseases. On the other hand, since the physiological effects of ghrelin have been studied exclusively in male mice, few studies have been conducted on gender differences in ghrelin reactivity. In this review, we describe (1) the characteristics of GHS-R1a, (2) the role of ghrelin in hypophagia due to stress or anticancer drugs, and (3) the gender differences in the physiological effects of GHS-R1a and the influence of stress on it.

Regulatory effects of ghrelin on endoplasmic reticulum stress, oxidative stress, and autophagy: Therapeutic potential

Ghrelin is a regulatory peptide that is the endogenous ligand of the growth hormone secretagogue 1a (GHS-R1a) which belongs to the G protein-coupled receptor family. Ghrelin and GHS-R1a are widely expressed in the central and peripheral tissues and play therapeutic potential roles in the cytoprotection of many internal organs. Endoplasmic reticulum stress (ERS), oxidative stress, and autophagy dysfunction, which are involved in various diseases. In recent years, accumulating evidence has suggested that ghrelin exerts protective effects by regulating ERS, oxidative stress, and autophagy in diverse diseases. This review article summarizes information about the roles of the ghrelin system on ERS, oxidative stress, and autophagy in multiple diseases. It is suggested that ghrelin positively affects the treatment of diseases and may be considered as a therapeutic drug in many illnesses.

Central and peripheral actions of melatonin on reproduction in seasonal and continuous breeding mammals

Under field conditions, especially for mammals that inhabit high latitudes, the regulation of seasonal breeding activity to ensure delivery of the young at the time most conducive to their survival is essential. This is most frequently accomplished by the annual reproductive cycle being linked to seasonal photoperiod changes which determine the nocturnal duration of the pineal melatonin signal. Mating can occur during any season that ensures spring/early summer delivery of the offspring. Thus, the season of mating is determined by the duration of pregnancy. The precise hormonal control of the annual cycle of reproduction by melatonin is accomplished at the level of the hypothalamo-pituitary axis which, in turn, determines the physiological state of the gonad and adnexa due to the regulation of pituitary gonadotrophin release. Many species are continuous rather than seasonal breeders. In these species, melatonin has a minor hormonal influence on the central regulation of reproduction but, nevertheless, its antioxidant functions at the level of the gonads support optimal reproductive physiology. Possibly like all cells, those in the ovary, e.g., granulosa cells and oocytes (less is known about melatonin synthesis by the testes or spermatogenic cells), synthesize melatonin which is used locally to combat free radicals and reactive nitrogen species which would otherwise cause oxidative/nitrosative stress to these critically important cells. Oxidative damage to the oocyte, zygote, blastocyst, etc., results in an abnormal fetus which is either sloughed or gives rise to an unhealthy offspring. The importance of the protection of the gametes (both oocytes and sperm) from oxidative molecular mutilation cannot be overstated. Fortunately, as a highly effective free radical scavenger and indirect antioxidant (by upregulating antioxidant enzyme), locally-produced melatonin is in the optimal location to protect the reproductive system from such damage.

Long-term effect of bariatric surgery on body composition in patients with morbid obesity: A systematic review and meta-analysis

We performed a meta-analysis to provide quantitative estimates of fat mass (FM) and fat-free mass (FFM) changes in patients following bariatric surgery over 1 year. A systematic search of PubMed, SCOPUS and Web of Science databases was conducted; the pooled weighted mean difference (WMD) and 95% confidence intervals (CI) were calculated using a random-effects model. Thirty-four studies including Roux en-Y gastric bypass (RYGB), sleeve gastrectomy (SG) biliopancreatic diversion (BPD) and gastric banding (GB) were analyzed. RYGB decreased in body FM (-28.99 kg [31.21, -26.77]) or FM% (-12.73% [-15.14, -10.32]) or FFM (-9.97 kg [-10.93, -9.03]), which were greater than SG and GB. Moreover, the FFM% in RYGB group (11.72% [7.33, 16.11]) was more than SG (5.7% [4.44, 6.95]) and GB (8.1% [6.15, 10.05]) groups. Bariatric surgeries, especially RYGB, might be effective for a decrease in FM and maintenance of FFM in patients with morbid obesity in over 1 year.

Plasma desacyl ghrelin-to-acyl ghrelin ratio is a predictor of postoperative complications and prognosis after pancreaticoduodenectomy

The current study aimed to clarify the significance of the preoperative desacyl ghrelin (DG)-to-acyl ghrelin (AG) ratio in patients undergoing pancreaticoduodenectomy (PD). Ghrelin, a peptide hormone mainly produced in the stomach, possesses unique functions. Recently, studies have determined the involvement of plasma gherlin in certain postoperative outcomes, particularly in surgical resections of the stomach. Although PD involves gastric resection, few reports have determined the involvement of ghrelin following PD. From April 2003 to December 2011, 195 patients underwent PD for tumors of the pancreatic head, bile duct and ampulla of Vater at the Division of Hepato-Biliary-Pancreatic Surgery, Department of Surgery, University of Miyazaki Faculty of Medicine (Miyazaki, Japan). Of these, 83 patients were enrolled into the present study as their plasma gherlin levels were measured. AG, DG, total ghrelin (TG) and the DG-to-AG ratio (D/A) were subsequently assessed. Furthermore, the prognostic nutritional index (PNI) and high-sensitivity modified Glasgow Prognostic Score (HS-mGPS) were determined. Morbidity was examined in all 83 patients, but mortality was only determined in 69 individuals after 14 patients were excluded due to the presence of benign disease. The results revealed that the TG of patients undergoing standard PD (SPD) was significantly lower than that of patients undergoing pylorus-preserving PD or subtotal stomach-preserving PD. It was also determined that TG levels declined significantly in SPD patients at 2 weeks after surgery. Negative associations were identified between plasma ghrelin levels and PNI, and between serum albumin and HS-mGPS. Patient morbidity was determined to be 31.3% and the severe complications exhibited by patients included pancreatic fistula (14.5%), intra-abdominal abscess (15.7%), intra-abdominal bleeding (6.0%) and liver abscess (1.2%). Multivariate analysis revealed that disease location and low D/A were independent risk factors for severe complications. The 5-year overall survival (OS) rate was 41.5%. Multivariate analysis also demonstrated that diabetes mellitus, long postoperative hospital stay and low D/A were independent risk factors for OS. The present study revealed the D/A may serve as a useful predictive factor for postoperative complications and prognosis after PD.

Sleeve Gastrectomy and Roux-En-Y Gastric Bypass Lead to Comparable Changes in Body Composition in a Multiethnic Asian Population

BACKGROUND

Changes in body composition after bariatric surgery such as a sustained loss of body fat are often associated with an inevitable loss of fat free mass. This can contribute to an undesirable disturbance in resting metabolic rate and weight maintenance. Our aim was to study changes in body composition in a multiethnic Asian cohort following bariatric surgery and to identify differences between laparoscopic sleeve gastrectomy and laparoscopic Roux-en-Y gastric bypass.

METHODS

A retrospective review of prospectively collected data on 295 patients who underwent either laparoscopic sleeve gastrectomy (256 patients) or laparoscopic Roux-en-Y gastric bypass (39 patients) was performed. Body composition variables were measured with the analyzer, GAIA 359 PLUS, which included the parameters; total body weight, body mass index, excess weight, basal metabolic rate, fat-free mass, fat mass, and total body water.

RESULTS

There were no statistical differences in gender, ethnicity, age, weight, height, and body mass index between laparoscopic sleeve gastrectomy and Roux-en-Y gastric bypass. At each time point (6, 12, 24, and 36 months) post-operation, there was no significant differences in % total body weight loss, basal metabolic rate, fat mass, fat percentage, and total body water between sleeve gastrectomy and bypass patients. There was significant difference (p < 0.05) in fat free mass only at 3 years post-operation, with sleeve gastrectomy patients having 9.79 kg less fat-free mass than bypass patients. However, after multivariate analysis, we found no statistically significant differences.

CONCLUSION

Sleeve gastrectomy and gastric bypass seemed to give similar changes to body composition.

Short-term outcomes and nutritional status after laparoscopic subtotal gastrectomy with a very small remnant stomach for cStage I proximal gastric carcinoma

BACKGROUND

Total or proximal gastrectomy is usually performed for early proximal gastric carcinoma, but the optimal type of gastrectomy is still unknown. We evaluated short-term outcomes and nutritional status after laparoscopic subtotal gastrectomy (LsTG) in comparison with laparoscopic total gastrectomy (LTG) and laparoscopic proximal gastrectomy (LPG).

METHODS

We analyzed 113 patients who underwent LsTG (n = 38), LTG (n = 48), or LPG (n = 27) for cStage I gastric cancer located in the upper third of the stomach. Postoperative morbidities, nutritional status including body weight, serum albumin, hemoglobin, the prognostic nutritional index (PNI), and endoscopic findings at 1 year after surgery were compared between LsTG and both LTG and LPG.

RESULTS

Operation time and intraoperative blood loss were similar among the three groups. The incidence of postoperative morbidities was lower in LsTG than in LTG. The degree of body weight loss was significantly smaller in LsTG than in LTG at 6 and 12 months. At 12 months, LsTG resulted in better serum albumin and PNI than LPG, and better hemoglobin than LTG. Endoscopic examination demonstrated that one LsTG patient and two LPG patients had reflux esophagitis. Remnant gastritis was observed more frequently in LPG than in LsTG. No LsTG patient had bile reflux, although it was observed in four LPG patients.

CONCLUSIONS

LsTG with a very small remnant stomach had favorable short-term outcomes and nutritional status compared with LTG and LPG, so it may be a better treatment option for cStage I proximal gastric carcinoma.

The Homeostatic Force of Ghrelin

Ghrelin, a gastric-derived acylated peptide, regulates energy homeostasis by transmitting information about peripheral nutritional status to the brain, and is essential for protecting organisms against famine. Ghrelin operates brain circuits to regulate homeostatic and hedonic feeding. Recent research advances have shed new light on ghrelin's multifaceted roles in cellular homeostasis, which could maintain the internal environment and overcome metaflammation in metabolic organs. Here, we highlight our current understanding of the regulatory mechanisms of the ghrelin system in energy metabolism and cellular homeostasis and its clinical trials. Future studies of ghrelin will further elucidate how the stomach regulates systemic homeostasis.

Synergistic effect of melatonin and ghrelin in preventing cisplatin-induced ovarian damage via regulation of FOXO3a phosphorylation and binding to the p27Kip1 promoter in primordial follicles

Premature ovarian failure during chemotherapy is a serious problem for young women with cancer. To preserve the fertility of these patients, approaches to prevent chemotherapy-induced ovarian failure are needed. In a previous study, we reported that melatonin treatment prevents the depletion of the dormant follicle pool via repression of the simultaneous activation of dormant primordial follicles by cisplatin. However, melatonin's protective effect was only partial and thus insufficient. In this study, we found that the hormone ghrelin enhances the protective effect of melatonin against cisplatin-induced ovarian failure in mouse model. Co-administration of melatonin and ghrelin more effectively prevented cisplatin-induced follicle disruption. Simultaneous treatment with melatonin and ghrelin almost restored the number of primordial follicles and the corpus luteum in cisplatin-treated ovaries, compared with single administration. We found melatonin and ghrelin receptors on the cell membrane of premature oocytes of primordial follicles. In addition, melatonin and ghrelin co-administration inhibited the cisplatin-induced phosphorylation of PTEN and FOXO3a that induces cytoplasmic translocation of FOXO3a. Inhibition of FOXO3a phosphorylation by melatonin and ghrelin increased the binding affinity of FOXO3a for the p27^Kip1 promoter in primordial follicles. Co-administration of melatonin and ghrelin in cisplatin-treated ovaries restored the expression of p27^Kip1 , which is critical for retention of the dormant status of primordial follicles. In conclusion, these findings suggest that melatonin and ghrelin co-administration is suitable for use as a fertoprotective adjuvant therapy during cisplatin chemotherapy in young female cancer patients.

Robotic valvuloplastic esophagogastrostomy using double flap technique following proximal gastrectomy: technical aspects and short-term outcomes

BACKGROUND

Valvuloplastic esophagogastrostomy by double flap technique (VEG-DFT) is a promising procedure to prevent reflux after proximal gastrectomy (PG), and is achieved by the burial of the abdominal esophagus into the gastric submucosa; however, laparoscopic VEG-DFT is technically demanding due to complicated suturing and ligation maneuvers. The present study was designed to determine the feasibility and safety of robotic VEG-DFT.

METHODS

After robotic PG, seromuscular flaps were extracorporeally created at the anterior wall of the remnant stomach through a small umbilical incision. Then, using a robot, the posterior wall of the esophagus was fixed to the cranial end of the mucosal window, and layer-to-layer sutures were placed between the anterior aspects of esophagus and the remnant stomach. Finally, the anastomosis was covered by seromuscular flaps. Short-term outcomes of 12 consecutive patients who underwent VEG-DFT between January 2014 and December 2015 were assessed.

RESULTS

Operations were successfully completed using robotic assistance in all patients. Median operative, surgeon console, and anastomosis times were 406 (324-613 min), 267 (214-483), and 104 (76-186) min, respectively, and median estimated blood loss was 31 (5-130) ml. The first six cases were required to reach a learning plateau. Both mortality and morbidity rates within 30 days after surgery were 0%. Postoperative hospital stay was 10 (9-30) days. No postoperative reflux esophagitis was observed, whereas anastomotic stenosis, which required endoscopic balloon dilation, developed in three patients (25%) in postoperative month 2. There was a significant association between the total number of stitches used for VEG-DFT and anastomotic stenosis (p < 0.001).

CONCLUSIONS

Robotic assistance may be useful for VEG-DFT with a short learning curve. Attention is required to prevent postoperative anastomotic stenosis possibly caused by an excessive number of stitches for esophagogastrostomy.

Ghrelin and the Cardiovascular System

Ghrelin is a small peptide released primarily from the stomach. It is a potent stimulator of growth hormone secretion from the pituitary gland and is well known for its regulation of metabolism and appetite. There is also a strong relationship between ghrelin and the cardiovascular system. Ghrelin receptors are present throughout the heart and vasculature and have been linked with molecular pathways, including, but not limited to, the regulation of intracellular calcium concentration, inhibition of proapoptotic cascades, and protection against oxidative damage. Ghrelin shows robust cardioprotective effects including enhancing endothelial and vascular function, preventing atherosclerosis, inhibiting sympathetic drive, and decreasing blood pressure. After myocardial infarction, exogenous administration of ghrelin preserves cardiac function, reduces the incidence of fatal arrhythmias, and attenuates apoptosis and ventricular remodeling, leading to improvements in heart failure. It ameliorates cachexia in end-stage congestive heart failure patients and has shown clinical benefit in pulmonary hypertension. Nonetheless, since ghrelin's discovery is relatively recent, there remains a substantial amount of research needed to fully understand its clinical significance in cardiovascular disease.

Changes in fat-soluble vitamin levels after gastrectomy for gastric cancer

Several authors have reported the relationship between gastric cancer risk and vitamins. However, there are few reports on fat-soluble vitamins after gastrectomy for gastric cancer. Fat malabsorption and suppression of food intake after gastrectomy for gastric cancer have been previously documented. Because of fat malabsorption and suppression of food intake, a potential deficiency in fat-soluble vitamins, such as vitamins A, D, E, and K, has been readily suggested. In about 20 % of patients, the serum vitamin E levels were decreased. Indeed, vitamin E deficiency is a common complication after gastrectomy. Continuous vitamin E deficiency could develop from neurological symptoms, i.e., peripheral neuropathy, limb or truncal ataxia. The total cholesterol level is associated with the vitamin E levels. However, the serum vitamin A levels were decreased in only 1.8 % of patients. In total gastrectomy cases, the serum vitamin A level may readily decrease. In contrast, 1,25(OH)₂ vitamin D deficiency, which is the most active vitamin D metabolite, is rare. Additionally, vitamin K deficiency after gastrectomy has not been reported thus far. Evidence that serum fat-soluble vitamin levels may decrease after gastrectomy for gastric cancer has not been established yet. Future research must explore fat-soluble vitamin deficiency after gastrectomy.

Postoperative Changes in Body Composition After Pancreaticoduodenectomy Using Multifrequency Bioelectrical Impedance Analysis

BACKGROUND

Nutritional status is one of the most important clinical determinants of outcome after surgery. The aim of this study was to compare changes in the body composition of patients undergoing pancreaticoduodenectomy (PD), distal gastrectomy (DG), or total gastrectomy (TG).

METHODS

The parameters of body composition were measured using multifrequency bioelectrical impedance analysis with an inBody 720 (Biospace Inc. Tokyo. Japan) in 60 patients who had undergone PD (n = 18), DG (n = 30), or TG (n = 12). None of the patients had recurrence or were treated with chemotherapy. Changes between the preoperative data and results and those obtained 12 months after surgery were evaluated.

RESULTS

Twelve months after surgery, the body weight change in the PD group was significantly lower than in the TG and DG groups (-1.2 ± 3.8 vs -7.4 ± 4.4 and -4.0 ± 3.2 kg, respectively; p < 0.01 vs TG, p < 0.05 vs DG). The body weight change correlated with the fat mass change in all groups.

CONCLUSIONS

The type and extent of surgery has a different effect on long-term body weight and body composition. Bioelectric impedance analysis can be used to assess body composition and may be useful for nutritional assessment in patients who have undergone these surgeries.

The Influence of Ghrelin on the Development of Dextran Sodium Sulfate-Induced Colitis in Rats

Ghrelin has protective and therapeutic effects in the gut. The aim of present studies was to investigate the effect of treatment with ghrelin on the development of colitis evoked by dextran sodium sulfate (DSS). Methods. Studies have been performed on rats. Colitis was induced by adding 5% DSS to the drinking water for 5 days. During this period animals were treated intraperitoneally twice a day with saline or ghrelin given at the dose of 8 nmol/kg/dose. On the sixth day, animals were anesthetized and the severity of colitis was assessed. Results. Treatment with ghrelin during administration of DSS reduced the development of colitis. Morphological features of colonic mucosa exhibited a reduction in the area and deep of mucosal damage. Ghrelin reversed the colitis-induced decrease in blood flow, DNA synthesis, and superoxide dismutase activity in colonic mucosa. These effects were accompanied by a decrease in the colitis-evoked increase in mucosal concentration of interleukin-1β and malondialdehyde. Treatment with ghrelin reversed the DSS-induced reduction in body weight gain. Conclusions. Administration of ghrelin exhibits the preventive effect against the development of DSS-induced colitis. This effect seems to be related to ghrelin's anti-inflammatory and antioxidative properties.

Potential benefits of laparoscopy-assisted proximal gastrectomy with esophagogastrostomy for cT1 upper-third gastric cancer

BACKGROUND

Few reports have compared laparoscopy-assisted proximal gastrectomy (LAPG) with laparoscopy-assisted total gastrectomy (LATG) in patients with cT1N0 gastric cancer. This study assessed the safety and feasibility of LAPG with esophagogastrostomy in these patients and compared postgastrectomy disturbances and nutritional status following LAPG and LATG.

METHODS

This study compared 40 patients who underwent LAPG with esophagogastrostomy and 59 who underwent LATG with esophagojejunostomy, both with OrVil™. Surgical outcomes, postoperative complications, nutritional status at 1 and 2 years, and relapse-free survival were compared in these two groups.

RESULTS

Operation time was significantly shorter in the LAPG group than in the LATG group (280 min vs. 365 min, P < 0.001). Although the rate of surgical complications was similar in the two groups, the rate of anastomotic stricture was significantly higher in the LAPG group than in the LATG group (28 vs. 8.4 %; P = 0.012). Rates of reflux esophagitis graded A or higher in the Los Angeles classification were 10 and 5.1 %, respectively. Hemoglobin levels 2 years after surgery, relative to baseline levels, were significantly higher in the LAPG group than in the LATG group (98.6 vs. 92.9 %, P = 0.020). Body weight, albumin and total protein concentrations, and total lymphocyte count 1 and 2 years after surgery were slightly, but not significantly, higher in the LAPG group. Relapse-free survival rates were similar, as were 5-year overall survival rates (86 vs. 79 %, P = 0.42).

CONCLUSIONS

LAPG with esophagogastrostomy using OrVil™ was safe and feasible for patients with cT1N0 gastric cancer. LAPG may have nutritional advantages over LATG, but the rate of anastomotic stricture was significantly higher for LAPG than for LATG.

Ghrelin - Physiological Functions and Regulation

Ghrelin is an orexigenic peptide predominantly secreted from the stomach and stimulates appetite and growth hormone (GH) release. Studies have provided evidence that ghrelin exercises a wide range of functions, including regulation of food intake and energy metabolism, modulation of cardiovascular function, stimulation of osteoblast proliferation and bone formation and stimulation of neurogenesis and myogenesis. In the gastrointestinal system, ghrelin affects multiple functions, including secretion of gastric acid, gastric motility and pancreatic protein output. Most of these functions have been attributed to the actions of acylated ghrelin. The balance among its secretion rate, degradation rate and clearance rate determines the circulating level of ghrelin. This review explains what ghrelin is, its physiological functions and the factors that influence its level.

Perturbation of acyl ghrelin profile after liver transplantation

BACKGROUND

A significant problem to be solved for patients after liver transplantation (LT) is malnutrition with anorexia in the early posttransplant period. We hypothesized that this problem was due to the change in ghrelin metabolism during LT. The aim of this study was to examine the balance of acyl ghrelin (AG) and desacyl ghrelin and the dependence of the regulation mechanism on hepatic-related enzymes in patients during LT.

MATERIALS AND METHODS

AG, desacyl ghrelin, and acyl/total ghrelin (A/T) concentrations in blood samples were measured in 15 patients with liver failure (LF), 15 patients after LT, and 10 controls. The correlations between the participants' ghrelin profiles and hepatic function-related data, including liver enzymes, were evaluated. In vitro assays using synthetic AG for assessment of deacylation activity in serum were performed.

RESULTS

AG and A/T ratio were significantly higher in the LF patients than the patients after LT and controls (AG: 25.9 ± 12.6 versus 16.4 ± 12.6 and 9.8 ± 7.6 fmol/mL, P < 0.05; A/T ratio: 17.4 ± 4.1 versus 12.2 ± 5.5 and 11.8% ± 5.9%, P < 0.05). The serum cholinesterase level was inversely correlated with AG and A/T ratio (P < 0.01). In vitro assays showed that deacylation activity was significantly lower in patients with LF than controls (10.5% versus 42.4%, 90 min; P < 0.01). Degradation of AG was partially suppressed by a cholinesterase inhibitor.

CONCLUSIONS

Deacylation activity was lower in LF patients, which could cause elevation of AG levels. Serum cholinesterase may be responsible for deacylation in humans.

Ghrelin administration suppresses inflammation-associated colorectal carcinogenesis in mice

Ghrelin is a 28-amino-acid peptide that stimulates the release of pituitary growth hormone. Because of its orexigenic effects, ghrelin is being developed as a therapeutic option for postoperative support and treatment of anorexia-cachexia syndrome of cancer patients. However, ghrelin has a multiplicity of physiological functions, and it also affects cell proliferation. Therefore, the effects of ghrelin administration on carcinogenesis and cancer progression in patients susceptible to cancer should be clarified. In this study, we examined the effects of ghrelin on cancer promotion in vivo using murine intestinal carcinogenesis models. Intestinal tumorigenesis was examined to determine the effects of either exogenous ghrelin administration or ghrelin deficiency following deletion of the Ghrl gene. Two murine intestinal tumorigenesis models were used. The first was the azoxymethane (AOM)/dextran sodium sulfate (DSS)-induced inflammation-associated colon carcinogenesis model and the second was the Apc^Min/+ genetic cancer susceptibility model. In AOM/DSS-treated mice, administration of ghrelin significantly suppressed tumor formation in the colon. In contrast, ghrelin administration did not affect the number of intestinal tumors formed in Apc^Min/+ mice. The absence of endogenous ghrelin did not affect the incidence of intestinal tumors in either AOM/DSS-treated mice or Apc^Min/+ mice, though tumor size tended to be larger in Ghrl^−/− colons in the AOM/DSS model. No tumor-promoting effect was observed by ghrelin administration in either tumorigenesis model. In summary, this study provides in vivo experimental evidence for the usefulness of ghrelin administration in the chemoprevention of inflammation-associated colorectal carcinogenesis and may suggest its safety in patients under colitis-associated cancer susceptibility conditions.

Impact of synthetic ghrelin administration for patients with severe body weight reduction more than 1 year after gastrectomy: a phase II clinical trial

PURPOSE

Ghrelin is mainly secreted from the stomach and plays a role in appetite, weight gain, and the promotion of a positive energy balance. The levels of ghrelin decrease immediately after gastrectomy. We herein investigated the effect of the administration of synthetic ghrelin to treat postoperative severe weight loss in a prospective, one-arm clinical trial to develop new strategies for weight gain.

METHODS

Ten patients (four distal gastrectomy and six total gastrectomy) received ghrelin treatment. Eligibility criteria included patients who underwent gastrectomy more than 1 year previously and 15 % body weight loss from the preoperative weight or a body mass index under 19. Synthetic human ghrelin (3 μg/kg) was administered to the patients twice a day for 1 week. Oral intake of calories, appetite [evaluated using the visual analog scale (VAS)], and body weight before and during administration of ghrelin were compared.

RESULTS

There was a significant difference in the oral food intake before and during treatment (before treatment: 1236 ± 409 kcal vs. during treatment: 1398 ± 365 kcal, p = 0.039), and the VAS for appetite significantly improved with each day of ghrelin administration (p < 0.05). Significant amounts of body weight were gained (39.5 ± 6.8 vs. 40.1 ± 6.9, p = 0.037).

CONCLUSIONS

The administration of synthetic ghrelin improved the food intake and was effective for treating appetite loss and body weight loss. Synthetic ghrelin may be a promising new therapy for severe body weight loss following gastrectomy.

Effects of sleeve gastrectomy and gastric banding on the hypothalamic feeding center in an obese rat model

PURPOSE

Laparoscopic sleeve gastrectomy (SG) and gastric banding (GB) are popular bariatric procedures for treating morbid obesity. This study aimed to investigate changes in the hypothalamic feeding center after these surgeries in a diet-induced obese rat model.

METHODS

Obesity was induced in 60 Sprague-Dawley rats using a high-energy diet for 6 weeks. These rats were divided into four groups: the sham-operated (SO) control, pair-fed (PF) control, SG and GB groups. Six weeks after the surgery, metabolic parameters, the plasma levels of leptin, ghrelin, peptide YY (PYY) and glucagon-like peptide-1 (GLP-1) and the hypothalamic mRNA expressions of neuropeptide Y (NPY) and pro-opiomelanocortin (POMC) were measured.

RESULTS

Compared with those observed in the SO group, the body and fat tissue weights were significantly decreased and the metabolic parameters were significantly improved in the PF, SG and GB groups 6 weeks after surgery. The plasma ghrelin levels were significantly lower and the PYY and GLP-1 levels were significantly higher in the SG group than in the PF, GB and SO groups. Compared with that seen in the PF and GB groups, the hypothalamic mRNA expression of NPY was significantly lower and the expression of POMC was significantly higher in the SG group.

CONCLUSIONS

SG may affect the neurological pathway associated with appetite in the hypothalamus and thereby control ingestive behavior.

Potential mechanisms mediating improved glycemic control after bariatric/metabolic surgery

Conservative medical treatment for morbid obesity generally fails to sustain weight loss. On the other hand, surgical operations, so-called bariatric surgery, have evolved due to their long-term effects. The global increase in the overweight population and the introduction of laparoscopic surgery have resulted in the use of bariatric surgery spreading quickly worldwide in recent years. Recent clinical evidence suggests that bariatric surgery not only reduces body weight, but also improves secondary serious diseases, including type 2 diabetes mellitus, in so-called metabolic surgery. Moreover, several potential mechanisms mediating the improvement in glycemic control after bariatric/metabolic surgery have been proposed based on the animal and human studies. These mechanisms include changes in the levels of gastrointestinal hormones, bacterial flora, bile acids, intestinal gluconeogenesis and gastrointestinal motility as well as adipose tissue and inflammatory mediators after surgery. The mechanisms underlying improved glycemic control are expected to accelerate the promotion of both metabolic and bariatric surgery. This article describes the current status of bariatric surgery worldwide and in Japan, reviews the accumulated data for weight loss and diabetic improvements after surgery and discusses the potential mechanisms mediating improved glycemic control.