Bone mineral metabolism after total gastrectomy

Malnutrition and vitamin deficiencies after surgery for esophageal and gastric cancer: A metanalysis

BACKGROUND & AIMS

Patients receiving oncological esophagectomy or gastrectomy are known to be at high risk for vitamin and micronutrient deficiency before, during and after surgery. However, there are no clear guidelines for these cancer patients regarding postoperative vitamin supplementation.

METHODS

We conducted a metanalysis consisting of 10 studies regarding vitamin and micronutrient deficiencies after oncological gastric or esophageal resection. 5 databases were searched.

RESULTS

Data was sufficient regarding Vitamins B12 and 25-OH D3 as well as calcium. We were able to show deficiencies in 25-OH Vitamin D3 levels (p < 0.001) and lower levels of Vitamin B12 and calcium (bit p < 0.001) when compared to the healthy population.

CONCLUSIONS

Patients from these groups are at risk for vitamin deficiencies. A guideline on postoperative supplementation is needed.

Effective Management of Sacral Stress Fractures in Gastric Cancer: Iliosacral Screw Fixation Following a Type 3 Hemipelvectomy

Metastatic pelvic tumors pose a significant challenge in oncologic orthopedics due to their complex management and the high potential for postoperative complications. This case study discusses a 75-year-old male with a sacral stress fracture following a type 3 internal hemipelvectomy for a metastatic lesion from gastric cancer in the left pubic bone. Initial conservative treatments failed to yield satisfactory improvement, leading to surgical intervention. Open reduction and internal fixation with an iliosacral screw, despite complications, significantly alleviated pain and improved mobility. This case underscores the difficulty in diagnosing sacral stress fractures versus metastatic lesions and highlights the effectiveness of iliosacral screw fixation in managing postoperative sacral stress fractures. It emphasizes the procedure's role in providing early pain relief and enhancing daily activity levels. Additionally, it points out the importance of addressing altered bone metabolism in the postoperative care of patients with metastatic pelvic tumors. This contributes to the literature by stressing the incidence of sacral stress fractures as a critical, though often overlooked, complication and demonstrating the benefits of iliosacral screw fixation in such scenarios for better recovery and quality of life.

From Cells to Environment: Exploring the Interplay between Factors Shaping Bone Health and Disease

The skeletal system is an extraordinary structure that serves multiple purposes within the body, including providing support, facilitating movement, and safeguarding vital organs. Moreover, it acts as a reservoir for essential minerals crucial for overall bodily function. The intricate interplay of bone cells plays a critical role in maintaining bone homeostasis, ensuring a delicate balance. However, various factors, both intrinsic and extrinsic, can disrupt this vital physiological process. These factors encompass genetics, aging, dietary and lifestyle choices, the gut microbiome, environmental toxins, and more. They can interfere with bone health through several mechanisms, such as hormonal imbalances, disruptions in bone turnover, direct toxicity to osteoblasts, increased osteoclast activity, immune system aging, impaired inflammatory responses, and disturbances in the gut-bone axis. As a consequence, these disturbances can give rise to a range of bone disorders. The regulation of bone's physiological functions involves an intricate network of continuous processes known as bone remodeling, which is influenced by various intrinsic and extrinsic factors within the organism. However, our understanding of the precise cellular and molecular mechanisms governing the complex interactions between environmental factors and the host elements that affect bone health is still in its nascent stages. In light of this, this comprehensive review aims to explore emerging evidence surrounding bone homeostasis, potential risk factors influencing it, and prospective therapeutic interventions for future management of bone-related disorders.

Bone mineral density, osteopenia and osteoporosis among US adults with cancer

BACKGROUND

Bone mineral deficits are one of the most common complications in cancer survivors. However, there are no studies evaluating bone mineral density (BMD) and the prevalence of osteopenia and osteoporosis among patients with different types of cancers.

AIM

The objective was to assess BMD and evaluate the prevalence of osteopenia and osteoporosis among US adults with cancer.

DESIGN

A cross-section propensity score matching study.

METHODS

We extracted data from National Health and Nutrition Examination Survey database from 2005 to 2018. We compared BMD in participants with and without cancer which was further analyzed according to cancer type. We conducted logistic regression to evaluate adjusted odds ratios of osteopenia and osteoporosis and determine risk factors for their development.

RESULTS

We found that BMD was significantly higher in participants without cancer than cancer patients. Furthermore, the median BMD of patients with breast cancer or skin cancer (including melanoma) was significantly lower than participants without cancer. People with breast, lung, genitourinary and skin cancers were more likely to incur osteopenia/osteoporosis than those without cancer.

CONCLUSIONS

BMD differs depending upon type in survivors. Individuals with a history of cancer have a poor understanding of osteoporosis and its risk factors. Understanding risk factors in patients with cancers identified in our study may be helpful for preventing osteoporosis and fractures and the development of screening guidelines.

Changes in bone mineral density after bariatric surgery in patients of different ages or patients with different postoperative periods: a systematic review and meta-analysis

To assess changes in bone mineral density (BMD) following bariatric surgery (BS) in patients with different bone sites, postoperative periods and ages. Twenty-two studies were included. Femoral neck (FN) BMD decreased after surgery (MD, - 0.05 g/cm², CI - 0.10 to - 0.01, P = 0.03). Postoperative BMD decreased more in the FN and lumbar spine (LS) of patients older than 40 (FNBMD, - 0.07 g/cm², CI - 0.13 to - 0.00, P = 0.04; LSBMD, - 0.03 g/cm², CI - 0.05 to - 0.00, P = 0.02) or patients with a postoperative time of greater than 12 months (FNBMD, - 0.06 g/cm², CI - 0.12 to - 0.01, P = 0.03; LSMD, - 0.04 g/cm², CI - 0.09 to 0.01, P = 0.12); therefore, post-BS bone loss should be monitored among patients in these groups. Longer follow-ups are needed to determine whether BMD changes or stabilizes.

Role of Dietary Supplements and Probiotics in Modulating Microbiota and Bone Health: The Gut-Bone Axis

Osteoporosis is characterized by an alteration of bone microstructure with a decreased bone mineral density, leading to the incidence of fragility fractures. Around 200 million people are affected by osteoporosis, representing a major health burden worldwide. Several factors are involved in the pathogenesis of osteoporosis. Today, altered intestinal homeostasis is being investigated as a potential additional risk factor for reduced bone health and, therefore, as a novel potential therapeutic target. The intestinal microflora influences osteoclasts’ activity by regulating the serum levels of IGF-1, while also acting on the intestinal absorption of calcium. It is therefore not surprising that gut dysbiosis impacts bone health. Microbiota alterations affect the OPG/RANKL pathway in osteoclasts, and are correlated with reduced bone strength and quality. In this context, it has been hypothesized that dietary supplements, prebiotics, and probiotics contribute to the intestinal microecological balance that is important for bone health. The aim of the present comprehensive review is to describe the state of the art on the role of dietary supplements and probiotics as therapeutic agents for bone health regulation and osteoporosis, through gut microbiota modulation.

Metabolic bone disorders after gastrectomy: inevitable or preventable?

Some authors have suggested that a relationship exists between gastrectomy for gastric cancer and metabolic bone disorders. However, few studies have investigated metabolic bone disorders after gastrectomy for gastric cancer in detail. Thus, we reviewed the findings of our recent prospective study and those of other reports on this subject. Osteoporosis and osteomalacia have been observed after gastrectomy and appear to be caused by reduced food intake and absorption, and steatorrhea. Moreover, the incidence of fracture is high after gastrectomy, although subtotal or total gastrectomy and reconstruction for gastric cancer have not been identified as significant risk factors for decreased bone mineral density (BMD). Recently, we reported that the BMD decreased significantly within 12 months after gastrectomy for gastric cancer in both male and female patients, but there was no significant gender-related difference in the rate of change in BMD. More than 1 year after gastrectomy, the steep decrease in the BMD stabilized and normal levels of 1,25(OH)₂ vitamin D₃ were maintained, despite the lack of precursor for 1,25(OH)₂ vitamin D₃ synthesis after gastrectomy. Alendronate therapy might be effective and prevent postgastrectomy metabolic bone disorders; however, the optimal treatment and prevention strategy for this bone disorder has not been delineated.

Incidence and risk factors of osteoporotic status in outpatients who underwent gastrectomy for gastric cancer

Background and Aim

Disorders in bone metabolism have long been recognized as typical sequelae of gastrectomy; however, the pathogenesis has not been fully elucidated, resulting in a variation of reported incidence. This study aimed to evaluate current bone health by measuring bone mineral density (BMD) in patients treated by gastrectomy for gastric cancer, with a focus on incidence and risk factors of osteoporosis.

Methods

The study enrolled 81 patients who underwent gastrectomy for gastric cancer at Kochi Medical School. BMD of the lumbar spine was measured by dual‐energy X‐ray mineral absorptiometry, with the results expressed as a percentage of the young adult mean (YAM). Clinical data were also obtained to investigate associations with BMD.

Results

Of the 81 study patients, 12 (14.8%) were deemed to have osteoporosis, defined by a percentage of YAM <70, with a dominance of females over males (66.7% vs 17.4%; P < 0.001). The median body weight, hemoglobin concentration, and serum alkaline phosphatase (ALP) level of the patients with osteoporosis was significantly lower than in those with a percentage of YAM ≥70 group (39.6 kg vs 53.1 kg, P < 0.001; 10.9 mg/dL vs 12.5 mg/dL, P = 0.010; 210 U/L vs 251 U/L, P = 0.002). Further analyses revealed a significant positive correlation between body weight and percentage of YAM (r = 0.441, P < 0.001). Despite the administration of bisphosphonates in these patients during this study, one acquired a bone fracture.

Conclusion

Osteoporosis was found in 14.8% of postoperative gastric cancer patients, with female gender, low body weight, and low ALP proposed as risk factors for osteoporosis and thus future bone fracture.

Helicobacter pylori Related Diseases and Osteoporotic Fractures (Narrative Review)

Osteoporosis (OP) and osteoporotic fractures (OFs) are common multifactorial and heterogenic disorders of increasing incidence. Helicobacter pylori (H.p.) colonizes the stomach approximately in half of the world's population, causes gastroduodenal diseases and is prevalent in numerous extra-digestive diseases known to be associated with OP/OF. The studies regarding relationship between H.p. infection (HPI) and OP/OFs are inconsistent. The current review summarizes the relevant literature on the potential role of HPI in OP, falls and OFs and highlights the reasons for controversies in the publications. In the first section, after a brief overview of HPI biological features, we analyze the studies evaluating the association of HPI and bone status. The second part includes data on the prevalence of OP/OFs in HPI-induced gastroduodenal diseases (peptic ulcer, chronic/atrophic gastritis and cancer) and the effects of acid-suppressive drugs. In the next section, we discuss the possible contribution of HPI-associated extra-digestive diseases and medications to OP/OF, focusing on conditions affecting both bone homeostasis and predisposing to falls. In the last section, we describe clinical implications of accumulated data on HPI as a co-factor of OP/OF and present a feasible five-step algorithm for OP/OF risk assessment and management in regard to HPI, emphasizing the importance of an integrative (but differentiated) holistic approach. Increased awareness about the consequences of HPI linked to OP/OF can aid early detection and management. Further research on the HPI-OP/OF relationship is needed to close current knowledge gaps and improve clinical management of both OP/OF and HPI-related disorders.

The change of bone mineral density and bone metabolism after gastrectomy for gastric cancer: a meta-analysis

Bone mineral density (BMD) is significantly decreased after gastrectomy in patients with gastric cancer. Calcium malabsorption, secondary hyperparathyroidism, and dominant bone resorption appear to contribute to bone loss in these patients. Patients should undergo early surveillance and nutritional or pharmacologic intensive interventions for bone health.

PURPOSE

Survivorship care, including bone health, has become an important issue in gastric cancer. We performed a meta-analysis of the available observational studies to determine whether and how osteoporosis risk is increased after gastrectomy in patients with gastric cancer.

METHODS

A total of 1204 patients (802 men) from 19 cohort studies were included. We evaluated the prevalence of osteoporosis in postgastrectomy patients, comparing the incidence according to the type of gastrectomy and sex. Additionally, we evaluated changes in bone mineral density (BMD) and bone metabolism-related markers pre- to postoperatively and between patients who underwent gastrectomy and matched controls. Proportion meta-analysis was performed and pooled odds ratios (ORs) were calculated.

RESULTS

The pooled incidence estimate was 36% [95% confidence interval (CI), 32-40]. The incidence of osteoporosis was significantly higher in women than in men (OR = 1.90, p < 0.001) but was similar between partial and total gastrectomy groups (OR = 0.983, p = 0.939). BMD was significantly decreased, and calcium, phosphorous, and parathyroid hormone levels were significantly increased in patients after gastrectomy compared to those before gastrectomy. BMD and calcium and 25OH-vitamin D levels were significantly decreased, and parathyroid hormone and 1,25OH-vitamin D levels were significantly increased in the gastrectomy group compared to that in the control group.

CONCLUSION

We found that BMD is significantly decreased after gastrectomy in patients with gastric cancer. Vitamin D deficiency and secondary hyperparathyroidism are suggested to be common mechanism underlying BMD impairment. After resection, patients should undergo long-term nutritional and bone health surveillance, in addition to their oncological follow-up.

Risk factors for loss of bone mineral density after curative esophagectomy

Micronutrient and fat malabsorption and altered enteroendocrine signaling occur after esophagectomy for cancer; however, the impact of malnutrition on bone health in this cohort has not been previously investigated. In this study, the prevalence of osteoporosis increased after curative surgery, associated with disease-specific, treatment-related, and population risk factors.

PURPOSE

Improved oncologic outcomes in esophageal cancer (EC) have resulted in increased survivorship and a focus on long-term quality of life. Malnutrition and micronutrient malabsorption are common among patients with EC, but the effect on bone metabolism is not known. The aim of this study was to characterize changes in bone mineral density (BMD) following curative esophagectomy.

METHODS

Consecutive disease-free patients who underwent esophagectomy with gastric conduit for pathologically node-negative disease from 2000 to 2014 were included. BMD was assessed at vertebral levels T12-L5 by computed tomography using a simple trabecular region-of-interest attenuation technique, and serum markers of nutritional status and bone metabolism were examined. Independent risk factors for osteoporosis were identified by multivariable logistic regression.

RESULTS

Seventy-five consecutive patients were studied. Osteoporosis was present in 25% at diagnosis. BMD declined at 1 and 2 years postoperatively (144.3 ± 45.8 versus 128.6 ± 46.2 and 122.7 ± 43.5 Hounsfield Units (HU), P < 0.0001), with increased osteoporosis prevalence to 38% and 44% (P = 0.049), respectively. No significant postoperative change in vitamin D, calcium, or phosphate was observed, but alkaline phosphatase increased significantly (P < 0.001). While female sex (P = 0.004) and ASA grade (P = 0.043) were independently associated with osteoporosis at diagnosis, age (P = 0.050), female sex (P = 0.023), smoking (P = 0.024), and pathologic T stage (P = 0.023) were independently predictive of osteoporosis at 1 year postoperatively.

CONCLUSIONS

Osteoporosis is prevalent among disease-free patients post-esophagectomy for EC, associated with disease-specific, treatment-related, and population risk factors. Strategies which minimize BMD decline should be considered to avoid fragility fractures in this cohort.

Increased Risk of Osteoporosis in Gastric Cancer Survivors Compared to General Population Control: A Study with Representative Korean Population

Purpose

Although several studies have suggested that osteoporosis is common in survivors of gastric cancer (GC), no study to date has directly assessed the risk for osteoporosis in GC survivors compared to matched controls. Thus, we aimed to investigate the relative risk for osteoporosis in survivors of GC compared to general population.

Materials and Methods

We used the Korea National Health and Nutrition Examination Survey data (2008-2011). Patients with a history of GC (n=94) were defined as case among 8,142 individuals over 50 years old who were evaluated by dual-energy X-ray absorptiometry. Controls (n=470) were matched to cases by age and sex in a 1:5 ratio. Osteopenia (–2.5 < T-score < –1.0) and osteoporosis (T-score ≤ –2.5) were defined.

Results

The prevalence of osteoporosis in GC survivors was 30.2%, which was significantly greater than that of controls (19.7%). In total, GC survivors had a 3.7-fold increased risk for osteoporosis compared to controls (p=0.021). In addition, the risk for osteoporosis of the total proximal femur total (TF) and femur neck (FN) was significantly increased among GC survivors compared to controls (adjusted relative risk, 4.64; 95% confidence interval, 1.16 to 18.6 in TF and adjusted relative risk, 3.58; 95% confidence interval, 1.19 to 10.8 in FN). Furthermore, we found sub-optimal daily calcium intake and mean serum levels of 25-hydroxy-vitamin D in both groups.

Conclusion

GC survivors are at significantly increased risk for osteoporosis, especially in the femur. Clinically, our finding supports the importance of screening bone health and adequate nutrient supplementation in survivors of GC.

Risk of osteoporosis after gastrectomy in long-term gastric cancer survivors

INTRODUCTION

Although early detection and successful gastrectomy have improved the survival of patients with gastric cancer, long-term health problems remain troubling. We evaluated the prevalence of osteoporosis and its risk factors in long-term survivors of gastric cancer after gastrectomy.

METHODS

We reviewed the medical records of a tertiary hospital between 2007 and 2014 to identify survivors of gastric cancer who had visited our center at around 5 years after gastrectomy. We evaluated their health status, including bone mineral density (BMD). Dual-energy X-ray absorptiometry was used to measure the BMD of the lumbar spine and femur (total and neck area). The prevalence of osteoporosis, defined by a BMD T score <-2.5, was investigated, and clinical variables associated with the presence of osteoporosis were identified.

RESULTS

A total of 250 survivors were included. The mean age was 54.6 years old, and the median follow-up was 6.0 years. The prevalence of osteoporosis was 34.0% (27.4% for men and 43.6% for women). Older age [odds ratio (OR) 5.50, 95% CI 2.33-13.00], higher alkaline phosphatase levels before gastrectomy (OR 5.67, 95% CI 1.36-23.64), and marked weight loss (≥20%) after gastrectomy (OR 3.59, 95% CI 1.32-9.77) were independently associated with the presence of osteoporosis.

CONCLUSIONS

In our cohort, osteoporosis was commonly observed in long-term survivors of gastric cancer, and several risk factors for it were identified. To reduce the risk of osteoporosis after gastrectomy, maintaining adequate body weight may be necessary.

Bone health in long-term gastric cancer survivors: A prospective study of high-dose vitamin D supplementation using an easy administration scheme

Bone disease in long-term survivors after gastric cancer resection has received little research attention. This study aimed to investigate bone health after curative resection of gastric cancer and the consequences of high-dose vitamin D supplementation in patients with low levels of 25-(OH)-vitamin D. Disease-free patients at least 24 months after gastric cancer resection represented the study cohort. Serum markers of bone metabolism were assessed at baseline and at 3 and 12 months. Bone mineral density and presence of fractures were assessed by X-ray at baseline. Patients with 25-(OH)-vitamin D ≤30 ng/mL at baseline received 16,000 IU of vitamin D3 every 10 days during the 1-year follow-up. Forty patients were included in the study. Mean time from surgery was 48.9 (24-109) months. Vitamin D insufficiency and secondary hyperparathyroidism were observed in 38 and 20 patients, respectively. Densitometry showed osteoporosis in 14 women and seven men and prevalent fractures in 12 women and six men at baseline. After 3 months of vitamin D supplementation, 35 patients reached values of 25-(OH)-vitamin D over 30 ng/mL. After 12 months, 38 patients were in the normal range of 25-(OH)-vitamin D. At the same time, iPTH levels and markers of bone turnover (C-terminal cross-linked telopeptide of type-I collagen, serum concentrations of bone-specific alkaline phosphatase and osteocalcin) significantly decreased after vitamin D intervention. Oral administration of high doses of vitamin D is easily implemented and restored 25-(OH)-vitamin D and iPTH values, which are frequently disturbed after gastric cancer resection.

Osteoporosis and fracture after gastrectomy for stomach cancer: A nationwide claims study

This study was planned to evaluate the incidence and risk factors of osteoporosis and fracture after gastrectomy for stomach cancer using a nationwide claims database in South Korea.Data from 41,512 patients (50-79 years) who underwent gastrectomy for stomach cancer from 2008 to 2010 with at least 5 years of follow-up were obtained from the Health Insurance Review and Assessment Service database. Patients diagnosed with osteoporosis and prescribed bisphosphonate or raloxifene or who experienced osteoporotic fractures after gastrectomy were operationally defined as osteoporosis. Osteoporotic fracture was defined as a fracture at common osteoporotic fracture sites (spine, pelvis, hip, forearm, or rib).In total, 37,076 patients were included in the final analysis. The incidences of postgastrectomy osteoporosis and osteoporotic fractures were 41.9 and 27.6 cases per 1000 person-years, respectively. Multivariate analysis showed that older age (hazard ratio [HR] 1.88; 95% confidence interval [CI] 1.79-1.96), female gender (HR 2.46; 2.35-2.58), total gastrectomy (HR 1.10; 1.04-1.16), and diabetes (HR 1.16; 1.11-1.22) were significantly associated with osteoporosis and that older age (HR 1.90; 95% CI 1.80-2.01), female gender (HR 1.50; 1.41-1.58), total gastrectomy (HR 1.17; 1.10-1.25), chemotherapy (HR 1.06; 1.00-1.12), and diabetes (HR 1.26; 1.19-1.33) were significantly associated with fractures. Osteoporotic fractures occurred a median 3.1 years after gastrectomy. Among the 5175 fracture patients, 780 (15.1%) experienced multisite fractures, mostly in the elderly and chemotherapy groups.The osteoporosis and osteoporotic fracture incidences are high in patients within a relatively short timeframe after gastrectomy for stomach cancer. Systematic management of osteoporosis is necessary after this surgery.

Bone mineral density after treatment for gastric cancer: Endoscopic treatment versus gastrectomy

Changes in bone metabolism among gastric cancer survivors have long been recognized. The aim of our study was to clarify the changes of bone mineral density (BMD) among gastric cancer survivors who underwent endoscopic resection or gastrectomy. Forty-nine patients diagnosed with tumor, node, and metastasis (TNM) stage 1 gastric cancer with pathologic confirmation, who underwent BMD measurement just before the procedure, and had no prior osteoporosis treatment, were studied. BMD was measured with dual energy x-ray absorptiometry before and after treatment. Laboratory tests were performed using fresh serum, and serum levels of alkaline phosphatase, albumin, calcium, and phosphorus were measured. We used a nested case-control design to compare groups. Of the 49 patients, 34 underwent gastrectomy and 15 underwent endoscopic treatment. There were no differences in baseline clinical characteristics, including BMD, and biochemical data between groups. The mean and median follow-up intervals for BMD measurement were 32.6 months (standard deviation, 16.5) and 31.0 months (interquartile range: 21.5, 41.0), respectively. The follow-up BMDs of the femoral neck and total hip were lower in the gastrectomy group (P = .010 and .011, respectively). The percentage changes in BMD for the lumbar spine, femoral neck, and total hip were -3.30%, -1.52%, and 0.40%, respectively, in the endoscopic treatment group, and -7.17%, -6.30%, and -3.49%, respectively, in the gastrectomy group. Bone loss of the lumbar spine and femoral neck were greater in the gastrectomy group (P = .028 and .022, respectively). BMD is lower after gastrectomy than after endoscopic treatment among early stage gastric cancer survivors.

Fundectomy-Evoked Osteopenia in Pigs Is Mediated by the Gastric-Hypothalamic-Pituitary Axis

The aim of the study was to determine the effects of gastric impairment in pigs on the axial and peripheral skeletal system properties and to test the hypothesis that fundectomy-evoked osteopenia is related to disturbed gastric-hypothalamic-pituitary axis function. Forty-day-old male piglets were subjected to experimental fundectomy (FX group, n = 6) to induce osteopenia, while sham operation was performed in the controls (SHO group, n = 6). At the age of 8 months, serum samples were collected, and the animals were sacrificed to obtain lumbar vertebrae (L1–L6) and right humerus for analysis. Using quantitative computed tomography (QCT) and dual-energy x-ray absorptiometry (DEXA) methods, bone mineral density and bone mineral content of the vertebrae and humerus were measured. The compression and three-point bending tests were applied to determine mechanical properties of lumbar vertebrae and humerus, respectively. Furthermore, geometric properties of humerus were assessed. Serum concentrations of ghrelin, growth hormone (GH), insulin-like growth factor-1 (IGF-1), and selected macro- and microelements were also determined. Performed fundectomy decreased body weight in pigs by 66% compared with pair-fed sham operated pigs ( P < 0.0001). Bone weight, bone mineral density, and bone mineral content of the lumbar vertebrae and humerus were significantly decreased in the fundectomized pigs ( P < 0.01). Mechanical parameters of the lumbar spine and humerus were decreased after the fundectomy, as well. Serum concentrations of ghrelin, GH, and IGF-1 were lowered by 74.4%, 90.6%, and 54.6% in the fundectomized pigs, respectively (all P < 0.001). Moreover, the serum concentrations of calcium, magnesium, iron and copper in the fundectomized animals were significantly decreased by 15.5%, 45.3%, 26.7%, and 26.2%, respectively ( P ≤ 0.05). In conclusion, the results obtained showed that both the disturbed gastric-hypothalamic-pituitary axis function and impaired mineral metabolism are associated with development of postfundectomy osteopenia of axial and peripheral skeleton in pigs.

The Korean Gastric Cancer Cohort Study: Study Protocol and Brief Results of a Large-Scale Prospective Cohort Study

Purpose

This study aimed to establish a large-scale database of patients with gastric cancer to facilitate the development of a national-cancer management system and a comprehensive cancer control policy.

Materials and Methods

An observational prospective cohort study on gastric cancer was initiated in 2010. A total of 14 cancer centers throughout the country and 152 researchers were involved in this study. Patient enrollment began in January 2011, and data regarding clinicopathological characteristics, life style-related factors, quality of life, as well as diet diaries were collected.

Results

In total, 4,963 patients were enrolled until December 2014, and approximately 5% of all Korean patients with gastric cancer annually were included. The mean age was 58.2±11.5 years, and 68.2% were men. The number of patients in each stage was as follows: 3,394 patients (68.4%) were in stage IA/B; 514 patients (10.4%), in stage IIA/B; 469 patients (9.5%), in stage IIIA/B/C; and 127 patients (2.6%), in stage IV. Surgical treatment was performed in 3,958 patients (79.8%), endoscopic resection was performed in 700 patients (14.1%), and 167 patients (3.4%) received palliative chemotherapy. The response rate for the questionnaire on the quality of life was 95%; however, diet diaries were only collected for 27% of patients.

Conclusions

To provide comprehensive information on gastric cancer for patients, physicians, and government officials, a large-scale database of Korean patients with gastric cancer was established. Based on the findings of this cohort study, an effective cancer management system and national cancer control policy could be developed.

Negative Effects of Total Gastrectomy on Bone Tissue Metabolism and Volumetric Bone Mineral Density (vBMD) of Lumbar Spine in 1-Year Study in Men

Gastrectomy induces severe osteoporosis in humans but its quantitative scale within trabecular and cortical compartments was not estimated. The aim of the study was to determine changes of volumetric bone mineral density (vBMD) in lumbar vertebrae (L1-L4) and biochemical bone metabolism markers in serum of patients 1 year after total gastrectomy. The control group consisted of patients (N = 8) subjected to abdominal surgery due to cardiospasmus. Total gastrectomy was performed in the experimental group (N = 6). Volumetric bone mineral density of trabecular and cortical bone of lumbar spine was measured before (baseline) and 1 year after the gastric surgery using the quantitative computed tomography method. Serum concentrations of insulin, insulin-like growth factor-1, tyroxine, interleukin-6, C-terminal telopeptides of type II collagen and bone formation, and resorption markers were determined at baseline and 1 year later, using ELISA, EIA, and IEMA methods. Total gastrectomy induced significant decrease of vBMD values, up to 16.8% and 10.0%, within the trabecular and cortical bone compartments of lumbar spine (P < 0.05). These negative changes of vBMD were associated with significantly increased serum concentration of bone resorption markers such as deoxypyridinoline, pyridinoline, and C-terminal telopeptides of type I collagen, by 13.5%, 32.2%, and 121.5%, respectively (P < 0.05). Neither vBMD nor biochemical bone turnover markers and hormone concentrations were influenced in the control patients. Dramatic bone loss during the first year in gastrectomized patients has proven dynamic osteoporosis progress indicating an importance of treatment interventions in these patients with emphasis on inhibition of intensive bone resorption processes.

The effect of supplementation of a glutamine precursor on the growth plate, articular cartilage and cancellous bone in fundectomy-induced osteopenic bone

The aim of the study was to investigate the effect of 2-oxoglutaric acid (2-Ox) supplementation (a precursor of glutamine and hydroxyproline, the most abundant amino acid of collagen) on cartilage and bone in pigs after fundectomy. Pigs at the age of forty days were subjected to fundectomy and divided into two groups depending on 2-Ox supplementation (at the daily dosage of 0.4 g/kg of body weight). Other pigs were sham operated. Pigs were euthanized at the age of eight months. An analysis of the morphometry of trabeculae, growth plate and articular cartilage in fundectomy-induced osteopenic bone was performed. Moreover, the levels of expression of osteocalcin, osteopontin and osteoprotegerin in trabecular bone and osteocalcin in articular cartilage were evaluated. Articular cartilage was thinnest in fundectomized pigs and thickest in 2-Ox-supplemented animals after fundectomy. Moreover, 2-Ox supplementation after fundectomy enhanced the total thickness of the growth plate and trabeculae in fundectomized pigs. The most evident signal for osteocalcin and osteoprotegerin in trabecular bone was in sham-operated and 2-Ox-supplemented pigs; a low reaction was observed in the fundectomized group. Additionally, as a long-term postoperative consequence, a change was observed in the expression of osteocalcin in articular cartilage. It seems that 2-Ox is suitable for use in preventing the negative effects of fundectomy on cancellous bone and cartilage.

Effects of total gastrectomy on plasma silicon and amino acid concentrations in men

The aim of the study was to determine one-year effects of total gastrectomy on plasma silicon and free amino acid concentrations in patients and evaluate changes of volumetric bone mineral density (vBMD) in lumbar spine. Eight patients were enrolled to the control (CTR) group. Six patients subjected to total gastrectomy (GX group) were included to the experimental group. vBMD in trabecular and cortical bone was measured in lumbar vertebrae at baseline (before surgery) and one year later using quantitative computed tomography. Plasma concentrations of silicon and free amino acids were determined at baseline and one year later using photometric method and ion-exchange chromatography. Body weights within CTR and GX groups were not different after one-year follow-up when compared to the baseline values (P > 0.05). An average annual decrease of vBMD in the trabecular bone in the gastrectomized patients reached 15.0% in lumbar spine and was significantly different in comparison to the percentage changes observed in CTR group (P = 0.02). One-year percentage change of vBMD in the cortical bone in L1 and L2 has shown significantly decreased values by 10.5 and 9.1% in the GX group when compared to the percentage change observed in the controls (P < 0.05). Plasma concentration of adipic acid was significantly higher by 101.6% one year after total gastrectomy procedure in the patients when compared to the baseline value (P = 0.01). Plasma concentration of silicon was significantly lowered by 26.7% one year after the total gastrectomy when compared to the baseline value (P = 0.009). Total gastrectomy in patients has induced severe osteoporotic changes in lumbar spine within one-year period. The observed osteoporotic changes were associated with decreased plasma concentration of silicon indicating importance of exocrine and endocrine functions of stomach for silicon homeostasis maintenance. Gastrectomy-induced bone loss was not related to decreased amino acid concentration in plasma obtained from overnight fasted patients.

Calcium gluconate supplementation is effective to balance calcium homeostasis in patients with gastrectomy

We demonstrate histological evidence for hyperparathyroidism in patients with gastrectomy. This is, at least in part, explained by impaired calcium absorption, resulting in mineralization defects and secondary hyperparathyroidism. Additionally, we demonstrate improved bone mineralization in patients with gastrectomy after gluconate therapy and showed the effectiveness of calcium gluconate over carbonate to balance impaired calcium hemostasis in mice.

INTRODUCTION

Gastrectomy and hypochlorhydria due to long-term proton pump inhibitor therapy are associated with increased fracture risk because of intestinal calcium malabsorption. Hence, our objectives were to histologically investigate bone metabolism in patients with gastrectomy and to analyze the impact of calcium gluconate supplementation on skeletal integrity in the setting of impaired gastric acidification.

METHODS

Undecalcified bone biopsies of 26 gastrectomized individuals were histologically analyzed. In the clinical setting, we retrospectively identified 5 gastrectomized patients with sufficient vitamin D level, who were additionally supplemented with calcium gluconate and had a real bone mineral density (aBMD) follow-up assessments. A mouse model of achlorhydria (ATP4b-/-) was used to compare the effect of calcium gluconate and calcium carbonate supplementation on bone metabolism.

RESULTS

Biopsies from gastrectomized individuals showed significantly increased osteoid, osteoclast, and osteoblast indices and fibroosteoclasia (p < 0.05) as well as impaired calcium distribution in mineralized bone matrix compared to healthy controls. Five gastrectomized patients with sufficient vitamin D level demonstrated a significant increase in aBMD after a treatment with calcium gluconate alone for at least 6 months (p < 0.05). Calcium gluconate was superior to calcium carbonate in maintaining calcium metabolism in a mouse model of achlorhydria.

CONCLUSION

Gastrectomy is associated with severe osteomalacia, marrow fibrosis, and impaired calcium distribution within the mineralized matrix. We show that calcium gluconate supplementation can increase bone mineral density in gastrectomized individuals and performs superior to calcium carbonate in restoring calcium/skeletal homoeostasis in a mouse model of achlorhydria.

The role of the gastrointestinal tract in calcium homeostasis and bone remodeling

While skeletal biology was approached in a rather isolated fashion in the past, an increasing understanding of the interplay between extraskeletal organs and bone remodeling has been obtained in recent years. This review will discuss recent advances in the field that have shed light on how the gastrointestinal tract and bone relate to each other. In particular, the importance of the GI tract in maintaining calcium homeostasis and skeletal integrity will be reviewed as impaired gastric acid production represents a major public health problem with possible implications for sufficient calcium absorption. Osteoporosis, the most prevalent bone disease worldwide, is caused not only by intrinsic defects affecting bone cell differentiation and function but also by a large set of extrinsic factors including hormonal disturbances, malnutrition, and iatrogenic drug application. Given the skeletal requirements of calcium, amino acids, and energy for bone turnover and renewal, it is not surprising that the gastrointestinal (GI) tract is of major importance for skeletal integrity.

A dairy product fermented by lactobacilli cancels the adverse effects of hypochlorhydria induced by a proton pump inhibitor on bone metabolism in growing rats

The purpose of the present study is to investigate the effects of hypochlorhydria induced by proton pump inhibitor (PPI) administration and intake of a dairy product fermented by lactobacilli (DFL) on bone metabolism in growing rats. Male rats, aged 3 weeks, were divided into two groups: a control group fed a casein-based diet and a group fed a DFL-based diet. Each group was fed its respective experimental diets for 9 d. At day 5 of the feeding period, each group was divided into two subgroups: one that received a saline injection and one that received a PPI injection. Rats were subcutaneously administered saline or PPI for 5 d. Faecal Ca excretion was determined from day 6 to day 9. At the end of the experiment, plasma and femurs were collected. Administration of PPI significantly decreased bone mineral density (shown by X-ray computerised tomography) and bone strength (shown by a three-point bending test) in the control group. Plasma osteocalcin, type I collagen C-telopeptides, 1,25-dihydroxyvitamin D and parathyroid hormone concentrations were elevated by PPI administration in the control group. Faecal Ca excretion and urinary P excretion in the control group were remarkably increased by PPI administration. On the other hand, these adverse effects of PPI were not observed in the DFL group. These results suggest that hypochlorhydria-induced bone loss may result from high bone turnover induced by secondary hyperparathyroidism due to Ca malabsorption and that DFL intake cancels these adverse effects probably via improving Ca malabsorption in growing rats.

Skeletal sequelae of cancer and cancer treatment

INTRODUCTION

Survivors of cancer may experience lingering adverse skeletal effects such as osteoporosis and osteomalacia. Skeletal disorders are often associated with advancing age, but these effects can be exacerbated by exposure to cancer and its treatment. This review will explore the cancer and cancer treatment-related causes of skeletal disorders.

METHODS

We performed a comprehensive search, using various Internet-based medical search engines such as PubMed, Medline Plus, Scopus, and Google Scholar, for published articles on the skeletal effects of cancer and cancer therapies.

RESULTS

One-hundred-forty-two publications, including journal articles, books, and book chapters, met the inclusion criteria. They included case reports, literature reviews, systematic analyses, and cohort reports. Skeletal effects resulting from cancer and cancer therapies, including hypogonadism, androgen deprivation therapy, estrogen suppression, glucocorticoids/corticosteroids, methotrexate, megestrol acetate, platinum compounds, cyclophosphamide, doxorubicin, interferon-alpha, valproic acid, cyclosporine, vitamin A, NSAIDS, estramustine, ifosfamide, radiotherapy, and combined chemotherapeutic regimens, were identified and described. Skeletal effects of hyperparathyroidism, vitamin D deficiency, gastrectomy, hypophosphatemia, and hyperprolactinemia resulting from cancer therapies were also described.

DISCUSSION/CONCLUSIONS

The publications researched during this review both highlight and emphasize the association between cancer therapies, including chemotherapy and radiotherapy, and skeletal dysfunction.

IMPLICATIONS FOR CANCER SURVIVORS

These studies confirm that cancer survivors experience a more rapid acceleration of bone loss than their age-matched peers who were never diagnosed with cancer. Further studies are needed to better address the skeletal needs of cancer survivors.

Chronic gastritis and bone mineral density in women

We conducted a cross-sectional study of bone mineral density in women with Helicobacter pylori gastritis or autoimmune gastritis. Eighty-five patients were enrolled: 24 patients (mean age 55.2 +/- 13.5 years) with autoimmune gastritis, 34 patients (mean age 63.7 +/- 7.3 years) with H. pylori gastritis, and 27 H. pylori-negative patients with normal gastric mucosa (mean age 62.5 +/- 7.0 years). Gastric mucosa was evaluated by histology and immunohistochemistry. Bone mineral density was measured by dual-energy X-ray absorptiometry. Autoimmune gastritis patients presented severe gastric body mucosa atrophy, based on the absence of parietal cells in 15 (62.5%) patients and the presence of only scattered parietal cells in the remaining nine (37.5%) patients. Among the H. pylori gastritis patients, 21 (62%) presented with different degrees of gastric mucosa atrophy. Bone mineral densities (mean +/- SD, g/mm(2)) were not different among patients with autoimmune gastritis and H. pylori gastritis and the controls. Our results suggest that H. pylori-associated gastritis and autoimmune gastritis would not to be risk factors for decreased bone mineral density in women.

3-Hydroxy-3-methylbutyrate administration diminishes fundectomy-induced osteopenia of the lumbar spine in pigs

OBJECTIVE

The aim of the study was to test the hypothesis that oral administration with 3-hydroxy-3-methylbutyrate (HMB) positively influences bone metabolism and diminishes fundectomy-induced osteopenia of the axial skeleton in pigs. The pig model was chosen because of its recognized physiologic and anatomic similarities of the gastrointestinal tract and skeletal system to those of humans.

METHODS

Eighteen male pigs were divided into three weight-matched groups at 40 d of life. Animals from the first and second groups were subjected to experimental fundectomy and the third group was sham operated. Starting the day after the fundectomy, the first and second groups received placebo and HMB, respectively. Animals were sacrificed at the age of 8 mo to obtain L(5) and L(6) vertebrae for analysis. The effects of HMB administration on plasma amino acids concentrations, bone mineral density, morphology, and mechanical properties of the lumbar vertebrae were determined.

RESULTS

The HMB treatment increased the weight of the vertebrae, bone mineral density, bone mineral content, total bone volume, trabecular bone mineral density, mean volumetric bone mineral density, calcium hydroxyapatite density in the trabecular and cortical bones, and plasma amino acid concentrations in the fundectomized pigs (P < 0.05). Mechanical strength of the spine, expressed by the values of ultimate force, Young's modulus, ultimate stress, stiffness, and work to the ultimate force point was increased in HMB-treated pigs (P < 0.05).

CONCLUSION

HMB administration to fundectomized pigs improved plasma amino acids concentrations and diminished development of fundectomy-induced osteopenia of the axial skeleton.

Mineral metabolism in obese patients following vertical banded gastroplasty

BACKGROUND

Bone disease has been described in patients after surgical treatment for obesity, but few studies have dealt with the impact of vertical banded gastroplasty on mineral metabolism. We have examined bone mineral metabolism in morbidly obese patients before and after 3 months after vertical banded gastroplasty without vitamin D supplementation.

METHODS

Sixteen morbidly obese patients (14 women, 2 men) with a mean (+/-SD) age of 38 +/- 9 years and a body mass index (BMI) of 47.1 +/- 8.1 kg/m2 were studied. No vitamin D supplementation was given. Body weight, fat mass, calcium, 25OHD, iPTH, bone remodeling markers, and leptin levels were measured at baseline and after weight loss.

RESULTS

Mean weight loss was 28 +/- 11 kg; BMI and body fat mass decreased by 20 and 35%, respectively. Bone resorption markers and albumin-corrected serum calcium increased after operation, whereas iPTH fell. Serum 25OHD levels rose. Leptin levels decreased. Serum iPTH was positively correlated with weight, BMI, and fat mass before operation (p < 0.05), and its decline after weight reduction was negatively associated with the increase in bone resorption markers (p < 0.01). Leptin concentration was correlated with BMI and body fat mass (p < 0.05) both before and after surgery.

CONCLUSIONS

Weight reduction obtained in morbidly obese subjects 3 months after vertical banded gastroplasty increases bone turnover markers and decreases PTH secretion. Serum 25OHD levels rose. Therefore, no reasons for a metabolic bone disease related to hypovitaminosis D were readily apparent. However, an increase in bone turnover, which is generally regarded as a potential risk factor for osteoporosis, was observed. Further work is needed to clarify the importance of this turnover increase in the long run.

Short-term changes in bone and mineral metabolism following gastrectomy in gastric cancer patients

Changes in bone and mineral metabolism that occur after gastrectomy have long been recognized. Gastrectomy has been identified as a risk factor for decreased bone mass and the increased fracture incidence. Previous investigations concerning postgastrectomy bone disease have been observational studies. No prospective studies have been reported that quantify the amount of bone loss after gastrectomy within the same patients. This study investigated 46 patients undergoing gastrectomy for gastric adenocarcinoma and analyzed 36 patients (58.1+/-10.8 years, 24 men and 12 women) who had dual energy X-ray absorptiometry (DXA) performed before and 1 year after gastrectomy. Systemic adjuvant chemotherapy was administered to 14 patients. Blood was sampled from all patients to determine serum calcium, phosphorous, and bone turnover marker levels before gastrectomy and at 1, 3, 6 and 12 months after surgery and for serum parathyroid hormone (PTH) and 25-hydroxyvitamin D levels before and 12 months after surgery. The mean bone loss in the lumbar spine, total hip, femoral neck, and trochanter, which was calculated as the percentage change from the baseline to the level measured at 12 months, was 5.7% (P<0.01), 5.4% (P<0.01), 6.6% (P<0.01) and 8.7% (P<0.01), respectively. Bone loss was generally greater in the group receiving chemotherapy. The serum calcium and phosphorous levels were not changed significantly and remained within the normal range throughout the observation period. After gastrectomy, the level of ICTP increased and reached a peak at 1 and 3 months, and progressively declined to baseline by 12 months. The osteocalcin levels were not coupled to an increase before 6 months. The level of 25-hydroxyvitamin D at 12 months postgastrectomy was not significantly changed compared to the baseline, however, the PTH levels increased by a mean of 63.6% at 12 months compared to the baseline (P<0.01). Significant correlations were found between the percent change in the BMD at the lumbar spine and total hip and the percentage change for the PTH level from their baselines to 12 months. The changes in the BMD at total hip, femoral neck, and trochanter also correlated to the change in body weight at 12 months. The data obtained by this study provides evidence that profound bone loss occurs in the setting of a bone remodeling imbalance during the early postgastrectomy period and allows the speculation that the gastrectomy related bone loss may be partially due to an overproduction of PTH.

High prevalence of osteoporosis in patients with gastric adenocarcinoma following gastrectomy

AIM: To evaluate the prevalence and predictive factors of osteoporosis in patients with gastric adenocarcinoma after gastrectomy.

METHODS: The study included 133 patients diagnosed with gastric adenocarcinoma but who did not undergo prior diagnostic work-up for osteoporosis. Bone mineral density (BMD) was measured by dual-energy X-ray absorptiometry (DXA) and vertebral deformity was assessed by plain X-rays. We evaluated the effects of age, sex, body mass index (BMI), anemia, back pain, vertebral deformity, tumor staging, reconstruction type, and past medical history to determine predictive factors of osteoporosis in these patients.

RESULTS: The prevalence of osteoporosis in the lumbar spine was 38.3% (male, 28.9%; female, 54.0%), and 15.0% in the femoral neck (male, 10.8%; female, 22.0%). The vertebral deformity rate was 46.6% (male, 43.4%; female, 52.0%). Age, BMI and hemoglobin correlated with BMD (P < 0.01). In males, anemia and age > 64 years were independent predictive factors of osteoporosis in multivariate analysis. In females, back pain was an independent factor for osteoporosis.

CONCLUSION: The results of this study revealed that prevalence of osteoporosis and vertebral bone deformity rate were high in gastric cancer patients, regardless of post-gastrectomy duration and operation type. Early diagnosis and a proper management plan must be established in these patients.

[Osteoporosis in cancer survivors]

The detection of late sequelae in survivors of cancer has become increasingly important as developments in diagnostic and therapeutic methods have led to a more and long-term survival rates in tumoral patients. Osteoporosis is one of such problem that has been increasingly identified in patients with cancer. Significant bone loss and increased risk of fractures have been described in these patients. Medical problems associated with the malignancy or caused by the oncologic treatment are the main factors involved in bone loss. Therefore, patients at risk for bone loss should be undergo preventive or therapeutic interventions at an early enough stage to prevent fractures.

Prevalence of vertebral alterations and the effects of calcium and vitamin D supplementation on calcium metabolism and bone mineral density after gastrectomy

Background

Bone disease is common after gastrectomy, resulting in decreased bone mass and an increased risk of fracture. No proven therapy is currently available.

Methods

Serum markers of calcium metabolism in 98 patients after partial or total gastrectomy were compared with those in 30 age- and sex-matched healthy controls. Patients with disorders of calcium metabolism were investigated by conventional radiography and single-energy computed tomography of the spine. Forty patients participated in a 1-year follow-up study to investigate the effects of vitamin D and calcium supplementation on calcium metabolism and bone mineral density.

Results

Altered serum markers of calcium and phosphate metabolism were observed in 77 (79 per cent) of 98 patients. Sixty (79 per cent) of these had vertebral alterations. Vertebral fractures were detected in 22 patients, grade I vertebral deformities in 50 patients, grade II deformities in 22 patients and osteopenia (Z-score less than − 1) in 30 patients. Calcium and vitamin D supplementation resulted in an increase in 25-hydroxy-vitamin D (P &lt; 0·001), 1,25-dihydroxy-vitamin D (P = 0·048) and osteocalcin (P = 0·045), whereas levels of parathyroid hormone were decreased (P = 0·007). Bone mineral density did not change over time.

Conclusion

Disturbances of calcium and bone metabolism are common after gastrectomy. Calcium and vitamin D supplementation normalized levels of markers of calcium metabolism and might have prevented age-related bone mass loss, although it did not increase bone mineral density after 1 year.

Postgastrectomy syndromes--diagnosis and treatment

The stomach has a variety of functions that are lost with gastrectomy. Since nowadays a significant number of patients are long-term survivors, consequences of this loss need to be considered by gastroenterologists and surgeons alike. Abnormal transit, disturbed general nutrition and micronutrient deficiencies are the most common problems. The main resulting symptoms are early and late dumping, reflux esophagitis, weight loss, anemia, and osteopathy. It is not definitively clear if pouch reconstruction can really improve the situation. Dietary measures, rarely re-operation, and in particular adequate follow-up of metabolic and nutrition parameters with consequent substitution are the main therapeutic necessities.

Urinary excretion of deoxypyridinoline increases after gastrointestinal surgery

OBJECTIVES

We investigated the effect of gastrointestinal surgery on bone metabolism with special reference to nutrition status and the systemic inflammatory response (SIR).

METHODS

We assessed bone resorption by measuring the urinary excretion of deoxypyridinoline (D-Pyr), a specific marker that reflects the amount of degraded collagen. Twenty patients who underwent gastrectomy or colectomy were enrolled in this study. Daily energy intake, nitrogen, calcium, and phosphate balances, and urinary D-Pyr were examined preoperatively and for 14 days after the operation. The nutritional risk index and prealbumin were measured for nutrition assessment, and SIR was evaluated daily based on scorings of body temperature, pulse rate, respiratory rate, and white blood cell number according to our criteria.

RESULTS

Urinary D-Pyr excretion had already increased on postoperative day 1 and continued to increase until postoperative day 14. The amounts of postoperative urinary excretion of D-Pyr correlated positively with the SIR scores and the amount of urinary excretion of cortisol, one of the stress-response hormones, and inversely with pre- and postoperative nutritional risk indices. In addition, the patients who experienced complications during the postoperative period excreted larger amounts of D-Pyr.

CONCLUSIONS

Because the amount of excreted D-Pyr reflects the loss of the bone matrix, these results may indicate that bone resorption increases after gastrointestinal surgery. The extent of resorption was parallel to the degree of SIR and nutrition status.

Genetics of osteoporosis

Osteoporosis is a common multifactorial disorder of reduced bone mass. The disorder in its most common form is generalized, affecting the elderly, both sexes, and all racial groups. Multiple environmental factors are involved in the pathogenesis. Genes also play a major role as reflected by heritability of many components of bone strength. Quantitative phenotypes in bone strength in the normal population do not conform to a monogenetic mode of inheritance. The common form of osteoporosis is generally considered to be a polygenic disorder arising from the interaction of common polymorphic alleles at quantitative trait loci, with multiple environmental factors. Finding the susceptibility genes underlying osteoporosis requires identifying specific alleles that coinherit with key heritable phenotypes in bone strength. Because of the close correspondence among mammalian genomes, identification of the genes underlying bone strength in mammals such as the mouse is likely to be of major assistance in human studies. Identification of susceptibility genes for osteoporosis is one of several important approaches toward the long-term goal of understanding the molecular biology of the normal variation in bone strength and how it may be modified to prevent osteoporosis. As with all genetic studies in humans, these scientific advances will need to be made in an environment of legal and ethical safeguards that are acceptable to the general public.

Neuroendocrine and peripheral activities of ghrelin: implications in metabolism and obesity

Ghrelin, a 28-amino acid acylated peptide predominantly produced by the stomach, displays strong growth hormone (GH)-releasing activity mediated by the hypothalamus-pituitary GH secretagogue (GHS)-receptors specific for synthetic GHS. The discovery of ghrelin definitely changes our understanding of GH regulation but it is also already clear that ghrelin is much more than simply a natural GHS. Ghrelin acts also on other central and peripheral receptors and shows other actions including stimulation of lactotroph and corticotroph secretion, orexia, influence on gastro-entero-pancreatic functions, metabolic, cardiovascular and anti-proliferative effects. GHS were born more than 20 years ago as synthetic molecules suggesting the option that GH deficiency could be treated by orally active GHS as an alternative to recombinant human GH (rhGH). Up to now, this has not been the case and also their usefulness as anabolic anti-aging intervention restoring GH/insulin-like growth factor-I axis in somatopause is still unclear. We are now confronted with the theoretical possibility that GHS analogues could become candidate drugs for treatment of pathophysiological conditions in internal medicine totally unrelated to disorders of GH secretion. Particularly, GHS receptor agonists or antagonists acting on appetite could represent new drug intervention in eating disorders.

Osteopenia and osteoporosis in gastrointestinal diseases: diagnosis and treatment

An increased awareness of the higher incidence of osteopenia and osteoporosis associated with a number of gastrointestinal disease states has occurred over the last few years. High rates of bone loss have been reported in luminal diseases such as inflammatory bowel disease and celiac disease as well as in cholestatic liver diseases and in the post-liver transplant setting. The post-gastrectomy state and chronic pancreatitis are also associated with decreased bone density. Publications over the last year have provided a better understanding of the true incidence of osteoporosis and fracture risk in these gastrointestinal disease states. Dual-energy x-ray absorptiometry remains the diagnostic procedure of choice. Biochemical markers of bone resorption have a role in identifying those patients with ongoing bone loss and monitoring their response to therapy. Identification of patients at risk and initiation of measures to prevent bone loss form the optimal therapeutic strategy. This article reviews advancements in the understanding of the development and activation of osteoblasts and osteoclasts. It also reviews the recent data concerning the diagnosis and treatment of bone loss associated with various gastrointestinal disease states.