Investigating the Stability, Variability and Mechanism of Incorporation of Lipid Mediators Into Eccrine Sweat

Not Applicable

Completed

Conditions: Stability & Variability of Lipid-derived Molecules in Sweat

Interventions: Drug: Ibuprofen
Other: Physiological induction of sweating
Drug: Pilocarpine

Registration Number: NCT02935894

Lead Sponsor: USDA, Western Human Nutrition Research Center

Brief Summary: The purpose of this study is to see what the differences are in sweat (amount and small molecule content) collected from different sites of the body and by different methods of sweat stimulation. Additionally, the investigators want to know whether the amount and small molecule content of the sweat is the same in an individual over time, and the same across individuals at a given time. Finally, the investigators want to know how consumption of over-the-counter anti-inflammatory drugs such as ibuprofen will affect the inflammatory mediator content of sweat and how that compares to blood. This information will help to better understand the composition and behavior of sweat and assess its potential utility as a routine clinical tool in skin research.

Detailed Description: Subjects will participate in 4 study day visits that will be scheduled about 1- week apart. During the first study visit, the investigators will compare sweat collected following pharmacological stimulation of sweating (using the drug pilocarpine) to sweat collected following physiological stimulation of sweating (using a stationary bicycle). During the second study visit, the investigators will collect sweat following stimulation of sweating by the drug pilocarpine from the inner part of the forearm (near the wrist) and also the upper surface of the thigh (near the knee). During the third study visit, the investigators will collect sweat following stimulation of sweating by the drug pilocarpine from the inner part of both forearms (near the wrist). During the fourth study visit, the investigators will collect a sweat sample following stimulation of sweating by the drug pilocarpine from the inner part of the forearm (near the wrist) and a blood sample (about one teaspoon) from the other arm. After blood and sweat collection, participants will consume 400 mg (two tablets) of ibuprofen. The investigators will then collect blood and sweat from 30 minutes, 2 hours and 4 hours after participants consume the ibuprofen.

Recruitment & Eligibility

Status: COMPLETED

Sex: Male

Target Recruitment: 14

Inclusion Criteria

20-40 y
Male
Weight > 110 pounds

Exclusion Criteria

Diagnosed active chronic diseases for which the individual is currently taking daily medication, including but not limited to:
- Diabetes mellitus
- Cardiovascular disease
- Cancer
- Gastrointestinal disorders
- Kidney disease
- Liver disease
- Bleeding disorders
- Asthma
- Autoimmune disorders
- Hypertension
- Osteoporosis
Recent minor surgery (within 4 wk) or major surgery (within 16 wk)
Recent antibiotic therapy (within 4 wk)
Recent hospitalization (within 4 wk)
Use of over-the-counter or prescription medications at the time of the study that directly affect endpoints of interest (e.g. hyperlipidemia, glycemic control, steroids, statins, anti-inflammatory agents, and weight loss aids)
Adults who are not able to consent
Under current medical supervision
Ibuprofen intolerance or allergy
Those with a bleeding disorder
Current enrollee in a clinical research study.
Individuals with blood clotting or platelet defect disorders
Individuals with orthopedic limitations or cardiovascular risk that preclude participation in the physiological stimulation of sweat by light exercise portion of the study
Individuals who are trained athletes or that regularly perform physical activity defined as "vigorous" by the Centers for Disease Control and Prevention

Study & Design

Study Type: INTERVENTIONAL

Study Design: SINGLE_GROUP

Arm && Interventions

Group	Intervention	Description
Single group	Physiological induction of sweating	All subjects will participate in 4 study day visits in the same order. 1. compare sweat collected following pharmacological stimulation of sweating (using the drug pilocarpine) to sweat collected following physiological induction of sweating (exercise using a stationary bicycle). 2. compare sweat collected following stimulation of sweating by the drug pilocarpine from the inner part of the forearm (near the wrist) to upper surface of thigh (near the knee). 3. collect sweat following stimulation of sweating by the drug pilocarpine from the inner part of both forearms (near the wrist). 4. collect blood and sweat samples before and 30 minutes, 2 hours and 4 hours after consumption of 400 mg of ibuprofen.
Single group	Ibuprofen	All subjects will participate in 4 study day visits in the same order. 1. compare sweat collected following pharmacological stimulation of sweating (using the drug pilocarpine) to sweat collected following physiological induction of sweating (exercise using a stationary bicycle). 2. compare sweat collected following stimulation of sweating by the drug pilocarpine from the inner part of the forearm (near the wrist) to upper surface of thigh (near the knee). 3. collect sweat following stimulation of sweating by the drug pilocarpine from the inner part of both forearms (near the wrist). 4. collect blood and sweat samples before and 30 minutes, 2 hours and 4 hours after consumption of 400 mg of ibuprofen.
Single group	Pilocarpine	All subjects will participate in 4 study day visits in the same order. 1. compare sweat collected following pharmacological stimulation of sweating (using the drug pilocarpine) to sweat collected following physiological induction of sweating (exercise using a stationary bicycle). 2. compare sweat collected following stimulation of sweating by the drug pilocarpine from the inner part of the forearm (near the wrist) to upper surface of thigh (near the knee). 3. collect sweat following stimulation of sweating by the drug pilocarpine from the inner part of both forearms (near the wrist). 4. collect blood and sweat samples before and 30 minutes, 2 hours and 4 hours after consumption of 400 mg of ibuprofen.

Primary Outcome Measures

Name	Time	Method
Volar Forearm Sweat Lipid Mediator Concentrations Following Pilocarpine Stimulation	measured at study visit 1, 2 and 3; detected lipid mediator concentrations for study visit 1 reported	Approximately 150 lipid mediators will be measured by liquid chromatography-tandem mass spectrometry (LC-MS/MS). Assayed lipid mediators include oxygenated lipids, endocannabinoids and endocannabinoid-like molecules, and sphingolipids.
Lower Back Sweat Lipid Mediator Concentrations Following Pilocarpine Stimulation	measured at study visit 1, detected lipid mediator concentrations reported	Approximately 150 lipid mediators will be measured by liquid chromatography-tandem mass spectrometry (LC-MS/MS). Assayed lipid mediators include oxygenated lipids, endocannabinoids and endocannabinoid-like molecules, and sphingolipids.
Volar Forearm Sweat Lipid Mediator Concentrations Following Exercise	measured at study visit 1, detected lipid mediator concentrations reported	Approximately 150 lipid mediators will be measured by liquid chromatography-tandem mass spectrometry (LC-MS/MS). Assayed lipid mediators include oxygenated lipids, endocannabinoids and endocannabinoid-like molecules, and sphingolipids.
Anterior Distal Thigh Sweat Lipid Mediator Concentrations Following Pilocarpine Stimulation	measured at study visit 2, detected lipid mediator concentrations reported	Approximately 150 lipid mediators will be measured by liquid chromatography-tandem mass spectrometry (LC-MS/MS). Assayed lipid mediators include oxygenated lipids, endocannabinoids and endocannabinoid-like molecules, and sphingolipids.
Change in Plasma Lipid Mediator Concentrations Before and After Oral Ibuprofen Administration	measured at four timepoints at study visit 4, detected lipid mediator concentrations for first timepoint reported	Approximately 100 lipid mediators will be measured by liquid chromatography-tandem mass spectrometry (LC-MS/MS). Assayed lipid mediators include oxygenated lipids, endocannabinoids, and endocannabinoid-like molecules.

Secondary Outcome Measures

Name	Time	Method
Change in Plasma Ibuprofen Concentrations	measured at four timepoints at study visit 4	Plasma concentration of ibuprofen prior to and 30 min, 2 hr and 4 hr after oral administration
Change in Pilocarpine-stimulated Sweat Lipid Mediator Concentrations Before and After Oral Ibuprofen Administration	measured at four timepoints at study visit 4, detected lipid mediator concentrations for first timepoint reported	Approximately 100 lipid mediators will be measured by liquid chromatography-tandem mass spectrometry (LC-MS/MS). Assayed lipid mediators include oxygenated lipids, endocannabinoids, and endocannabinoid-like molecules.
Change in Sweat Ibuprofen Concentrations	measured at four timepoints at study visit 4	Sweat concentration of ibuprofen prior to and 30 min, 2 hr and 4 hr after oral administration