The study “ Rose Hip and Its Constituent Galactolipids Confer Cartilage Protection by Modulating Cytokine and Chemokine Expression” by Schwager et al. (2011) looked at how rose hip powder (RHP) and a plant fat called galactolipid GLGPG affect inflammation in three kinds of cells. The team set out to determine why earlier clinical studies showed that rose hip helps people with osteoarthritis (OA). The summary that follows paraphrases the team’s results. They tested whether RHP and GLGPG could suppress inflammatory signals and slow cartilage breakdown in lab-grown cells. The authors note that “clinical studies have demonstrated a beneficial effect of rose hip powder (RHP) in the treatment of OA,” yet the exact compounds and pathways behind that effect were still unclear at the time of the study.

According to the scientific paper, OA happens when the cushion between joints, called cartilage, breaks down. The breakdown is caused by enzymes that cleave the building blocks of cartilage, including collagen and proteoglycans. The main enzyme groups involved are matrix metalloproteinases (MMPs) and aggrecanases (ADAMTS family).

The authors highlight that “interleukin (IL)-1β is considered a key catabolic factor that induces ECM degradation.” This means IL-1β, a chemical messenger, kicks off most of the damage. It also triggers the release of nitric oxide (NO), prostaglandin E2 (PGE2), and signaling proteins called chemokines, which attract more inflammatory cells into the joint. The team wanted to see if RHP and GLGPG could block these signals at their source.

The researchers ran two sets of lab tests using three cell types:

1. Mouse macrophage cells (RAW264.7) and human peripheral blood leukocytes (PBL), both triggered with bacterial lipopolysaccharide (LPS) to mimic inflammation.
2. Human chondrosarcoma cells (SW1353) and normal human articular chondrocytes from the knee (NHAC-kn), both triggered with IL-1β to mimic OA conditions.

Cells were treated with different doses of RHP or GLGPG. The team then measured NO, PGE2, and a panel of cytokines and chemokines using the Griess reaction, enzyme immunoassay (EIA), and multiplex enzyme-linked immunosorbent assay (ELISA). They also measured the activity of certain genes using reverse transcription polymerase chain reaction (RT-PCR).

The scientific paper reports that RHP and GLGPG reduced inflammation and slowed cartilage breakdown across all cell types tested.

In LPS-treated mouse macrophages, RHP reduced NO production with an IC50 of 797 mg/L and PGE2 production with an IC50 of 594 mg/L. GLGPG was much more potent per weight, lowering NO to an IC50 of 28.6 mg/L. Both compounds also reduced gene activity for inducible nitric oxide synthase (iNOS), and “expression of the anti-inflammatory IL-10 was increased by both substances.”

In human PBL, RHP significantly reduced the production of two key chemokines, CCL5/RANTES and CXCL10/IP-10. It also reduced tumor necrosis factor alpha (TNF-α) and interleukin-12 (IL-12). GLGPG followed a different pattern and lowered IL-1β, IL-6, and the chemokines monocyte chemoattractant protein-1 (MCP-1) and macrophage inflammatory protein-1α (MIP-1α). Both compounds increased granulocyte-macrophage colony-stimulating factor (GM-CSF) levels, a chondrocyte growth factor.

In SW1353 cells, RHP reduced gene expression of MMP-1, MMP-3, and MMP-13, the enzymes that cleave collagen. It also lowered five chemokine genes (MIP-2, MIP-3α, IL-8, CCL5/RANTES, and CXCL10/IP-10) along with IL-1α, IL-1β, and IL-6. In primary knee chondrocytes (NHAC-kn), RHP cut MMP-1, MMP-3, MMP-9, and MMP-13 expression by up to 75%. GLGPG had weaker effects in chondrocytes, which led the authors to conclude that “RHP, which presumably contains other chondro-protective substances besides GLGPG.”

RHP also reduced the activity of nuclear factor kappa B (NF-κB) signaling proteins, including NF-κB1, NF-κBp65, and I-κBα. This pathway controls many inflammatory genes, so blocking it likely accounts for a large share of the broad anti-inflammatory effects observed across the three cell types.

The scientific paper suggests three ways RHP and GLGPG may help with arthritis. First, they reduce NO and IL-1β, thereby slowing the early stages of cartilage breakdown. Second, they shift the balance between pro-inflammatory and anti-inflammatory cytokines, which calms the joint environment. Third, they lower chemokines that pull neutrophils and other immune cells into the joint.

The authors are honest about the work's limitations. They write that “the absence of data on bioavailability and pharmacokinetics of the substances makes it difficult to correlate the described in vitro effects with in vivo efficacy.” In plain terms, lab cell results do not always match what happens in the human body. The doses used in the lab were also high, and it is unclear if eating rose hips would deliver enough of these compounds to joint tissues. The team also flags a potential conflict of interest: “This research was funded by DSM Nutritional Products, where all authors are currently employed.”

Even with those caveats, the study offers a possible biological reason for why some people with arthritis report relief from rose hip supplements. The authors call for clinical trials to test whether these effects translate to real patients.

This 2011 scientific paper tested rose hip powder and its galactolipid, GLGPG, on three cell types associated with joint inflammation. Both substances reduced inflammatory signals such as NO, PGE2, TNF-α, IL-1β, and several chemokines, and they slowed gene expression of cartilage-cutting MMPs. RHP worked more broadly than GLGPG alone, suggesting that rose hip contains several active compounds that work together. The summary above paraphrases the authors’ findings, which suggest a possible molecular basis for the joint relief reported in earlier clinical studies of RHP. Larger human trials are still needed to confirm whether these lab effects hold up in real patients.